From f9ab71424471dca1735f19509add6d6892403dfd Mon Sep 17 00:00:00 2001
From: arnaudgolfouse <arnaud.golfouse@laposte.net>
Date: Mon, 11 Dec 2023 15:24:39 +0100
Subject: [PATCH] Change some tests to pass with final borrows

---
 creusot/tests/should_succeed/100doors.mlcfg   |   2 +-
 creusot/tests/should_succeed/all_zero.mlcfg   |   4 +-
 creusot/tests/should_succeed/bdd.mlcfg        |  14 +-
 creusot/tests/should_succeed/bug/682.mlcfg    |   2 +-
 creusot/tests/should_succeed/bug/766.mlcfg    |   2 +-
 .../should_succeed/closures/01_basic.mlcfg    |   2 +-
 .../should_succeed/closures/05_map.mlcfg      |   2 +-
 creusot/tests/should_succeed/drop_pair.mlcfg  |   2 +-
 creusot/tests/should_succeed/hashmap.mlcfg    |  16 +-
 creusot/tests/should_succeed/hillel.mlcfg     |  50 +-
 .../tests/should_succeed/index_range.mlcfg    |  10 +-
 .../inplace_list_reversal.mlcfg               |   2 +-
 .../should_succeed/invariant_moves.mlcfg      |   2 +-
 .../iterators/02_iter_mut.mlcfg               | 312 ++++++------
 .../should_succeed/iterators/02_iter_mut.rs   |  10 +-
 .../iterators/02_iter_mut/why3session.xml     |   8 +-
 .../iterators/03_std_iterators.mlcfg          | 110 ++---
 .../should_succeed/iterators/04_skip.mlcfg    |   4 +-
 .../should_succeed/iterators/05_map.mlcfg     |   6 +-
 .../iterators/06_map_precond.mlcfg            | 462 +++++++++---------
 .../iterators/06_map_precond.rs               |   1 -
 .../should_succeed/iterators/07_fuse.mlcfg    |   6 +-
 .../iterators/08_collect_extend.mlcfg         |   6 +-
 .../should_succeed/iterators/10_once.mlcfg    |   2 +-
 .../should_succeed/iterators/12_zip.mlcfg     |   6 +-
 .../should_succeed/iterators/13_cloned.mlcfg  |   4 +-
 .../should_succeed/iterators/14_copied.mlcfg  |   4 +-
 .../iterators/15_enumerate.mlcfg              |   4 +-
 .../should_succeed/iterators/16_take.mlcfg    |   4 +-
 .../tests/should_succeed/knapsack_full.mlcfg  |   4 +-
 .../should_succeed/lang/branch_borrow_2.mlcfg |  10 +-
 .../tests/should_succeed/list_index_mut.mlcfg |  12 +-
 .../should_succeed/list_reversal_lasso.mlcfg  |  20 +-
 .../tests/should_succeed/mapping_test.mlcfg   |   2 +-
 .../should_succeed/projection_toggle.mlcfg    |  14 +-
 .../tests/should_succeed/projections.mlcfg    |   2 +-
 .../tests/should_succeed/red_black_tree.mlcfg | 116 ++---
 .../tests/should_succeed/resolve_uninit.mlcfg |   8 +-
 creusot/tests/should_succeed/result/own.mlcfg |   8 +-
 .../should_succeed/rusthorn/inc_max.mlcfg     |  14 +-
 .../should_succeed/rusthorn/inc_max_3.mlcfg   |  18 +-
 .../rusthorn/inc_max_many.mlcfg               |  14 +-
 .../rusthorn/inc_max_repeat.mlcfg             |  16 +-
 .../rusthorn/inc_some_2_list.mlcfg            |   8 +-
 .../rusthorn/inc_some_2_tree.mlcfg            |  14 +-
 .../rusthorn/inc_some_list.mlcfg              |  18 +-
 .../rusthorn/inc_some_tree.mlcfg              |  24 +-
 .../selection_sort_generic.mlcfg              |   4 +-
 .../tests/should_succeed/sparse_array.mlcfg   |   6 +-
 .../tests/should_succeed/split_borrow.mlcfg   |   2 +-
 creusot/tests/should_succeed/sum.mlcfg        |   2 +-
 .../tests/should_succeed/sum_of_odds.mlcfg    |   2 +-
 .../tests/should_succeed/swap_borrows.mlcfg   |   2 +-
 .../should_succeed/syntax/05_pearlite.mlcfg   |   4 +-
 .../tests/should_succeed/take_first_mut.mlcfg |  12 +-
 .../tests/should_succeed/take_first_mut.rs    |   2 +-
 .../type_invariants/borrows.mlcfg             |  40 +-
 creusot/tests/should_succeed/unnest.mlcfg     |   2 +-
 creusot/tests/should_succeed/vector/01.mlcfg  |   2 +-
 .../vector/03_knuth_shuffle.mlcfg             |   2 +-
 .../vector/06_knights_tour.mlcfg              |  52 +-
 .../should_succeed/vector/08_haystack.mlcfg   |   4 +-
 .../should_succeed/vector/09_capacity.mlcfg   |   4 +-
 63 files changed, 761 insertions(+), 762 deletions(-)

diff --git a/creusot/tests/should_succeed/100doors.mlcfg b/creusot/tests/should_succeed/100doors.mlcfg
index 6c168f51b5..af9c28992c 100644
--- a/creusot/tests/should_succeed/100doors.mlcfg
+++ b/creusot/tests/should_succeed/100doors.mlcfg
@@ -1357,7 +1357,7 @@ module C100doors_F
   BB7 {
     _14 <- Borrow.borrow_mut iter;
     iter <-  ^ _14;
-    _13 <- Borrow.borrow_mut ( * _14);
+    _13 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _13) ; };
     _12 <- ([#"../100doors.rs" 20 4 20 41] Next0.next _13);
     _13 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/all_zero.mlcfg b/creusot/tests/should_succeed/all_zero.mlcfg
index ba88e33b32..4e919899f2 100644
--- a/creusot/tests/should_succeed/all_zero.mlcfg
+++ b/creusot/tests/should_succeed/all_zero.mlcfg
@@ -172,9 +172,9 @@ module AllZero_AllZero
     goto BB5
   }
   BB5 {
-    value <- Borrow.borrow_mut (AllZero_List_Type.cons_0 ( * loop_l));
+    value <- Borrow.borrow_final (AllZero_List_Type.cons_0 ( * loop_l)) (Borrow.inherit_id (Borrow.get_id loop_l) 1);
     loop_l <- { loop_l with current = (let AllZero_List_Type.C_Cons a b =  * loop_l in AllZero_List_Type.C_Cons ( ^ value) b) ; };
-    next <- Borrow.borrow_mut (AllZero_List_Type.cons_1 ( * loop_l));
+    next <- Borrow.borrow_final (AllZero_List_Type.cons_1 ( * loop_l)) (Borrow.inherit_id (Borrow.get_id loop_l) 2);
     loop_l <- { loop_l with current = (let AllZero_List_Type.C_Cons a b =  * loop_l in AllZero_List_Type.C_Cons a ( ^ next)) ; };
     value <- { value with current = ([#"../all_zero.rs" 44 17 44 18] (0 : uint32)) ; };
     assume { Resolve0.resolve value };
diff --git a/creusot/tests/should_succeed/bdd.mlcfg b/creusot/tests/should_succeed/bdd.mlcfg
index e21c4a7ccb..564184f6e5 100644
--- a/creusot/tests/should_succeed/bdd.mlcfg
+++ b/creusot/tests/should_succeed/bdd.mlcfg
@@ -3023,7 +3023,7 @@ module Bdd_Impl11_Hashcons
   BB5 {
     r1 <- Bdd_Bdd_Type.C_Bdd ( * _19) (Bdd_Context_Type.context_cnt ( * self));
     assume { Resolve1.resolve _19 };
-    _24 <- Borrow.borrow_mut (Bdd_Context_Type.context_hashcons ( * self));
+    _24 <- Borrow.borrow_final (Bdd_Context_Type.context_hashcons ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let Bdd_Context_Type.C_Context a b c d e f =  * self in Bdd_Context_Type.C_Context a ( ^ _24) c d e f) ; };
     _23 <- ([#"../bdd.rs" 446 8 446 31] Add0.add _24 n r1);
     _24 <- any borrowed (Bdd_Hashmap_MyHashMap_Type.t_myhashmap (Bdd_Node_Type.t_node) (Bdd_Bdd_Type.t_bdd));
@@ -3220,7 +3220,7 @@ module Bdd_Impl11_Node
     goto BB5
   }
   BB3 {
-    _17 <- Borrow.borrow_mut ( * self);
+    _17 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _17) ; };
     assume { Inv0.inv ( ^ _17) };
     _0 <- ([#"../bdd.rs" 469 8 469 50] Hashcons0.hashcons _17 (Bdd_Node_Type.C_If x childt childf));
@@ -3352,7 +3352,7 @@ module Bdd_Impl11_True
     goto BB0
   }
   BB0 {
-    _6 <- Borrow.borrow_mut ( * self);
+    _6 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _6) ; };
     assume { Inv0.inv ( ^ _6) };
     _0 <- ([#"../bdd.rs" 477 8 477 27] Hashcons0.hashcons _6 (Bdd_Node_Type.C_True));
@@ -3481,7 +3481,7 @@ module Bdd_Impl11_False
     goto BB0
   }
   BB0 {
-    _6 <- Borrow.borrow_mut ( * self);
+    _6 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _6) ; };
     assume { Inv0.inv ( ^ _6) };
     _0 <- ([#"../bdd.rs" 485 8 485 28] Hashcons0.hashcons _6 (Bdd_Node_Type.C_False));
@@ -3642,7 +3642,7 @@ module Bdd_Impl11_V
     goto BB2
   }
   BB2 {
-    _10 <- Borrow.borrow_mut ( * self);
+    _10 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _10) ; };
     assume { Inv0.inv ( ^ _10) };
     _0 <- ([#"../bdd.rs" 494 8 494 26] Node0.node _10 x t f);
@@ -3955,7 +3955,7 @@ module Bdd_Impl11_Not
     goto BB16
   }
   BB16 {
-    _35 <- Borrow.borrow_mut (Bdd_Context_Type.context_not_memo ( * self));
+    _35 <- Borrow.borrow_final (Bdd_Context_Type.context_not_memo ( * self)) (Borrow.inherit_id (Borrow.get_id self) 4);
     self <- { self with current = (let Bdd_Context_Type.C_Context a b c d e f =  * self in Bdd_Context_Type.C_Context a b c ( ^ _35) e f) ; };
     _34 <- ([#"../bdd.rs" 516 8 516 31] Add0.add _35 x r1);
     _35 <- any borrowed (Bdd_Hashmap_MyHashMap_Type.t_myhashmap (Bdd_Bdd_Type.t_bdd) (Bdd_Bdd_Type.t_bdd));
@@ -4657,7 +4657,7 @@ module Bdd_Impl11_And
     goto BB33
   }
   BB33 {
-    _79 <- Borrow.borrow_mut (Bdd_Context_Type.context_and_memo ( * self));
+    _79 <- Borrow.borrow_final (Bdd_Context_Type.context_and_memo ( * self)) (Borrow.inherit_id (Borrow.get_id self) 5);
     self <- { self with current = (let Bdd_Context_Type.C_Context a b c d e f =  * self in Bdd_Context_Type.C_Context a b c d ( ^ _79) f) ; };
     _78 <- ([#"../bdd.rs" 560 8 560 36] Add0.add _79 (a, b) r1);
     _79 <- any borrowed (Bdd_Hashmap_MyHashMap_Type.t_myhashmap (Bdd_Bdd_Type.t_bdd, Bdd_Bdd_Type.t_bdd) (Bdd_Bdd_Type.t_bdd));
diff --git a/creusot/tests/should_succeed/bug/682.mlcfg b/creusot/tests/should_succeed/bug/682.mlcfg
index c9b67c8185..24bb9300f7 100644
--- a/creusot/tests/should_succeed/bug/682.mlcfg
+++ b/creusot/tests/should_succeed/bug/682.mlcfg
@@ -104,7 +104,7 @@ module C682_Foo
     goto BB1
   }
   BB1 {
-    _7 <- Borrow.borrow_mut ( * a);
+    _7 <- Borrow.borrow_final ( * a) (Borrow.get_id a);
     a <- { a with current = ( ^ _7) ; };
     _6 <- ([#"../682.rs" 14 4 14 15] AddSome0.add_some _7);
     _7 <- any borrowed uint64;
diff --git a/creusot/tests/should_succeed/bug/766.mlcfg b/creusot/tests/should_succeed/bug/766.mlcfg
index 271c8c0347..2400f5e581 100644
--- a/creusot/tests/should_succeed/bug/766.mlcfg
+++ b/creusot/tests/should_succeed/bug/766.mlcfg
@@ -189,7 +189,7 @@ module C766_Trait_Goo
     goto BB0
   }
   BB0 {
-    _2 <- Borrow.borrow_mut ( * self);
+    _2 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _2) ; };
     assume { Inv0.inv ( ^ _2) };
     _0 <- ([#"../766.rs" 11 8 11 16] F0.f _2);
diff --git a/creusot/tests/should_succeed/closures/01_basic.mlcfg b/creusot/tests/should_succeed/closures/01_basic.mlcfg
index c0e54ed250..f795fe8cc5 100644
--- a/creusot/tests/should_succeed/closures/01_basic.mlcfg
+++ b/creusot/tests/should_succeed/closures/01_basic.mlcfg
@@ -508,7 +508,7 @@ module C01Basic_MoveMut_Closure0
     goto BB1
   }
   BB1 {
-    _2 <- Borrow.borrow_mut ( * _3);
+    _2 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _2) ; };
     _1 <- { _1 with current = (let C01Basic_MoveMut_Closure0 a =  * _1 in C01Basic_MoveMut_Closure0 _2) ; };
     _2 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/closures/05_map.mlcfg b/creusot/tests/should_succeed/closures/05_map.mlcfg
index 8812cdd018..1ac0a34971 100644
--- a/creusot/tests/should_succeed/closures/05_map.mlcfg
+++ b/creusot/tests/should_succeed/closures/05_map.mlcfg
@@ -962,7 +962,7 @@ module C05Map_Impl0_Next
     goto BB0
   }
   BB0 {
-    _3 <- Borrow.borrow_mut (C05Map_Map_Type.map_iter ( * self));
+    _3 <- Borrow.borrow_final (C05Map_Map_Type.map_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C05Map_Map_Type.C_Map a b =  * self in C05Map_Map_Type.C_Map ( ^ _3) b) ; };
     assume { Inv0.inv ( ^ _3) };
     _2 <- ([#"../05_map.rs" 18 14 18 30] Next0.next _3);
diff --git a/creusot/tests/should_succeed/drop_pair.mlcfg b/creusot/tests/should_succeed/drop_pair.mlcfg
index cec4c24d44..be26dda1ca 100644
--- a/creusot/tests/should_succeed/drop_pair.mlcfg
+++ b/creusot/tests/should_succeed/drop_pair.mlcfg
@@ -163,7 +163,7 @@ module DropPair_Drop
   }
   BB0 {
     assume { Resolve0.resolve _x };
-    _3 <- Borrow.borrow_mut ( * y);
+    _3 <- Borrow.borrow_final ( * y) (Borrow.get_id y);
     y <- { y with current = ( ^ _3) ; };
     _x <- _3;
     _3 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/hashmap.mlcfg b/creusot/tests/should_succeed/hashmap.mlcfg
index fd270632a7..f10880d71e 100644
--- a/creusot/tests/should_succeed/hashmap.mlcfg
+++ b/creusot/tests/should_succeed/hashmap.mlcfg
@@ -1782,7 +1782,7 @@ module Hashmap_Impl5_Add
     index <- ([#"../hashmap.rs" 110 27 110 55] UIntSize.of_int (UInt64.to_int _13) % _15);
     _13 <- any uint64;
     _15 <- any usize;
-    _20 <- Borrow.borrow_mut (Hashmap_MyHashMap_Type.myhashmap_buckets ( * self));
+    _20 <- Borrow.borrow_final (Hashmap_MyHashMap_Type.myhashmap_buckets ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let Hashmap_MyHashMap_Type.C_MyHashMap a =  * self in Hashmap_MyHashMap_Type.C_MyHashMap ( ^ _20)) ; };
     assume { Inv1.inv ( ^ _20) };
     _19 <- ([#"../hashmap.rs" 111 39 111 58] IndexMut0.index_mut _20 index);
@@ -1790,10 +1790,10 @@ module Hashmap_Impl5_Add
     goto BB5
   }
   BB5 {
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     assume { Inv2.inv ( ^ _18) };
-    l <- Borrow.borrow_mut ( * _18);
+    l <- Borrow.borrow_final ( * _18) (Borrow.get_id _18);
     _18 <- { _18 with current = ( ^ l) ; };
     assume { Inv2.inv ( ^ l) };
     assert { [@expl:type invariant] Inv3.inv _18 };
@@ -1825,13 +1825,13 @@ module Hashmap_Impl5_Add
     goto BB10
   }
   BB10 {
-    k <- Borrow.borrow_mut (let (a, _) = Hashmap_List_Type.cons_0 ( * l) in a);
+    k <- Borrow.borrow_final (let (a, _) = Hashmap_List_Type.cons_0 ( * l) in a) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id l) 1) 1);
     l <- { l with current = (let Hashmap_List_Type.C_Cons a b =  * l in Hashmap_List_Type.C_Cons (let (a, b) = Hashmap_List_Type.cons_0 ( * l) in ( ^ k, b)) b) ; };
     assume { Inv6.inv ( ^ k) };
-    v <- Borrow.borrow_mut (let (_, a) = Hashmap_List_Type.cons_0 ( * l) in a);
+    v <- Borrow.borrow_final (let (_, a) = Hashmap_List_Type.cons_0 ( * l) in a) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id l) 1) 2);
     l <- { l with current = (let Hashmap_List_Type.C_Cons a b =  * l in Hashmap_List_Type.C_Cons (let (a, b) = Hashmap_List_Type.cons_0 ( * l) in (a,  ^ v)) b) ; };
     assume { Inv7.inv ( ^ v) };
-    tl <- Borrow.borrow_mut (Hashmap_List_Type.cons_1 ( * l));
+    tl <- Borrow.borrow_final (Hashmap_List_Type.cons_1 ( * l)) (Borrow.inherit_id (Borrow.get_id l) 2);
     l <- { l with current = (let Hashmap_List_Type.C_Cons a b =  * l in Hashmap_List_Type.C_Cons a ( ^ tl)) ; };
     assume { Inv8.inv ( ^ tl) };
     tl1 <- tl;
@@ -1875,7 +1875,7 @@ module Hashmap_Impl5_Add
     _46 <- Borrow.borrow_mut ( * tl1);
     tl1 <- { tl1 with current = ( ^ _46) ; };
     assume { Inv2.inv ( ^ _46) };
-    _45 <- Borrow.borrow_mut ( * _46);
+    _45 <- Borrow.borrow_final ( * _46) (Borrow.get_id _46);
     _46 <- { _46 with current = ( ^ _45) ; };
     assume { Inv2.inv ( ^ _45) };
     assert { [@expl:type invariant] Inv3.inv l };
@@ -2785,7 +2785,7 @@ module Hashmap_Impl5_Resize
     _28 <- Borrow.borrow_mut ( * _29);
     _29 <- { _29 with current = ( ^ _28) ; };
     assume { Inv5.inv ( ^ _28) };
-    _27 <- Borrow.borrow_mut ( * _28);
+    _27 <- Borrow.borrow_final ( * _28) (Borrow.get_id _28);
     _28 <- { _28 with current = ( ^ _27) ; };
     assume { Inv5.inv ( ^ _27) };
     l <- ([#"../hashmap.rs" 177 33 177 83] Replace0.replace _27 (Hashmap_List_Type.C_Nil));
diff --git a/creusot/tests/should_succeed/hillel.mlcfg b/creusot/tests/should_succeed/hillel.mlcfg
index c704f1c2e0..fe321db1cc 100644
--- a/creusot/tests/should_succeed/hillel.mlcfg
+++ b/creusot/tests/should_succeed/hillel.mlcfg
@@ -1459,7 +1459,7 @@ module CreusotContracts_Std1_Slice_Impl14_Produces
   predicate produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t)
     
    =
-    [#"../../../../creusot-contracts/src/std/slice.rs" 379 12 379 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
+    [#"../../../../creusot-contracts/src/std/slice.rs" 380 12 380 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
   val produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t) : bool
     ensures { result = produces self visited tl }
     
@@ -1775,10 +1775,10 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl_Interface
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   type t
@@ -1787,12 +1787,12 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   clone CreusotContracts_Std1_Slice_Impl14_Produces_Stub as Produces0 with
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : () =
-    [#"../../../../creusot-contracts/src/std/slice.rs" 383 4 383 10] ()
+    [#"../../../../creusot-contracts/src/std/slice.rs" 384 4 384 10] ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Stub
   type t
@@ -1820,14 +1820,14 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Interface
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   type t
@@ -1842,16 +1842,16 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
    =
-    [#"../../../../creusot-contracts/src/std/slice.rs" 388 4 388 10] ()
+    [#"../../../../creusot-contracts/src/std/slice.rs" 389 4 389 10] ()
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module Hillel_InsertUnique_Interface
   type t
@@ -2307,7 +2307,7 @@ module Hillel_InsertUnique
   BB13 {
     _30 <- Borrow.borrow_mut iter;
     iter <-  ^ _30;
-    _29 <- Borrow.borrow_mut ( * _30);
+    _29 <- Borrow.borrow_final ( * _30) (Borrow.get_id _30);
     _30 <- { _30 with current = ( ^ _29) ; };
     _28 <- ([#"../hillel.rs" 84 4 84 111] Next0.next _29);
     _29 <- any borrowed (Core_Slice_Iter_Iter_Type.t_iter t);
@@ -2387,7 +2387,7 @@ module Hillel_InsertUnique
     goto BB12
   }
   BB24 {
-    _49 <- Borrow.borrow_mut ( * vec);
+    _49 <- Borrow.borrow_final ( * vec) (Borrow.get_id vec);
     vec <- { vec with current = ( ^ _49) ; };
     assume { Inv8.inv ( ^ _49) };
     _48 <- ([#"../hillel.rs" 94 4 94 18] Push0.push _49 elem);
@@ -3262,7 +3262,7 @@ module Hillel_Unique
   BB11 {
     _25 <- Borrow.borrow_mut iter;
     iter <-  ^ _25;
-    _24 <- Borrow.borrow_mut ( * _25);
+    _24 <- Borrow.borrow_final ( * _25) (Borrow.get_id _25);
     _25 <- { _25 with current = ( ^ _24) ; };
     _23 <- ([#"../hillel.rs" 104 4 104 48] Next0.next _24);
     _24 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
@@ -3310,7 +3310,7 @@ module Hillel_Unique
     _37 <- Borrow.borrow_mut unique;
     unique <-  ^ _37;
     assume { Inv2.inv ( ^ _37) };
-    _36 <- Borrow.borrow_mut ( * _37);
+    _36 <- Borrow.borrow_final ( * _37) (Borrow.get_id _37);
     _37 <- { _37 with current = ( ^ _36) ; };
     assume { Inv2.inv ( ^ _36) };
     assert { [@expl:type invariant] Inv3.inv elem };
@@ -3896,7 +3896,7 @@ module Hillel_Fulcrum
   BB5 {
     _21 <- Borrow.borrow_mut iter;
     iter <-  ^ _21;
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     _19 <- ([#"../hillel.rs" 159 4 159 60] Next0.next _20);
     _20 <- any borrowed (Core_Slice_Iter_Iter_Type.t_iter uint32);
@@ -3965,7 +3965,7 @@ module Hillel_Fulcrum
   BB17 {
     _52 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _52;
-    _51 <- Borrow.borrow_mut ( * _52);
+    _51 <- Borrow.borrow_final ( * _52) (Borrow.get_id _52);
     _52 <- { _52 with current = ( ^ _51) ; };
     _50 <- ([#"../hillel.rs" 171 4 171 58] Next1.next _51);
     _51 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/index_range.mlcfg b/creusot/tests/should_succeed/index_range.mlcfg
index 4774faca69..1ae5e2d66c 100644
--- a/creusot/tests/should_succeed/index_range.mlcfg
+++ b/creusot/tests/should_succeed/index_range.mlcfg
@@ -1662,7 +1662,7 @@ module IndexRange_TestRange
     goto BB54
   }
   BB54 {
-    s2 <- Borrow.borrow_mut ( * _105);
+    s2 <- Borrow.borrow_final ( * _105) (Borrow.get_id _105);
     _105 <- { _105 with current = ( ^ s2) ; };
     _111 <- ([#"../index_range.rs" 60 12 60 19] Len0.len ( * s2));
     goto BB55
@@ -2290,7 +2290,7 @@ module IndexRange_TestRangeTo
     goto BB23
   }
   BB23 {
-    s1 <- Borrow.borrow_mut ( * _44);
+    s1 <- Borrow.borrow_final ( * _44) (Borrow.get_id _44);
     _44 <- { _44 with current = ( ^ s1) ; };
     _50 <- ([#"../index_range.rs" 100 12 100 19] Len0.len ( * s1));
     goto BB24
@@ -2948,7 +2948,7 @@ module IndexRange_TestRangeFrom
     goto BB28
   }
   BB28 {
-    s1 <- Borrow.borrow_mut ( * _54);
+    s1 <- Borrow.borrow_final ( * _54) (Borrow.get_id _54);
     _54 <- { _54 with current = ( ^ s1) ; };
     _60 <- ([#"../index_range.rs" 139 12 139 19] Len0.len ( * s1));
     goto BB29
@@ -3542,7 +3542,7 @@ module IndexRange_TestRangeFull
     goto BB26
   }
   BB26 {
-    s1 <- Borrow.borrow_mut ( * _43);
+    s1 <- Borrow.borrow_final ( * _43) (Borrow.get_id _43);
     _43 <- { _43 with current = ( ^ s1) ; };
     _49 <- ([#"../index_range.rs" 166 12 166 19] Len0.len ( * s1));
     goto BB27
@@ -4143,7 +4143,7 @@ module IndexRange_TestRangeToInclusive
     goto BB19
   }
   BB19 {
-    s1 <- Borrow.borrow_mut ( * _35);
+    s1 <- Borrow.borrow_final ( * _35) (Borrow.get_id _35);
     _35 <- { _35 with current = ( ^ s1) ; };
     _41 <- ([#"../index_range.rs" 196 12 196 19] Len0.len ( * s1));
     goto BB20
diff --git a/creusot/tests/should_succeed/inplace_list_reversal.mlcfg b/creusot/tests/should_succeed/inplace_list_reversal.mlcfg
index c54c32e462..022b34d656 100644
--- a/creusot/tests/should_succeed/inplace_list_reversal.mlcfg
+++ b/creusot/tests/should_succeed/inplace_list_reversal.mlcfg
@@ -192,7 +192,7 @@ module InplaceListReversal_Rev
     assert { [@expl:type invariant] Inv0.inv old_l };
     assume { Resolve0.resolve old_l };
     prev <- InplaceListReversal_List_Type.C_Nil;
-    _7 <- Borrow.borrow_mut ( * l);
+    _7 <- Borrow.borrow_final ( * l) (Borrow.get_id l);
     l <- { l with current = ( ^ _7) ; };
     assume { Inv1.inv ( ^ _7) };
     head <- ([#"../inplace_list_reversal.rs" 27 19 27 34] Replace0.replace _7 (InplaceListReversal_List_Type.C_Nil));
diff --git a/creusot/tests/should_succeed/invariant_moves.mlcfg b/creusot/tests/should_succeed/invariant_moves.mlcfg
index 4511bf29df..000beda38a 100644
--- a/creusot/tests/should_succeed/invariant_moves.mlcfg
+++ b/creusot/tests/should_succeed/invariant_moves.mlcfg
@@ -488,7 +488,7 @@ module InvariantMoves_TestInvariantMove
   BB3 {
     _6 <- Borrow.borrow_mut x;
     x <-  ^ _6;
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     _4 <- ([#"../invariant_moves.rs" 7 26 7 40] Pop0.pop _5);
     _5 <- any borrowed (Alloc_Vec_Vec_Type.t_vec uint32 (Alloc_Alloc_Global_Type.t_global));
diff --git a/creusot/tests/should_succeed/iterators/02_iter_mut.mlcfg b/creusot/tests/should_succeed/iterators/02_iter_mut.mlcfg
index f52c094699..c8949dd3e5 100644
--- a/creusot/tests/should_succeed/iterators/02_iter_mut.mlcfg
+++ b/creusot/tests/should_succeed/iterators/02_iter_mut.mlcfg
@@ -134,28 +134,6 @@ module C02IterMut_Impl0_Invariant
   val invariant' [#"../02_iter_mut.rs" 20 4 20 30] (self : C02IterMut_IterMut_Type.t_itermut t) : bool
     ensures { result = invariant' self }
     
-end
-module CreusotContracts_Resolve_Impl1_Resolve_Stub
-  type t
-  use prelude.Borrow
-  predicate resolve (self : borrowed t)
-end
-module CreusotContracts_Resolve_Impl1_Resolve_Interface
-  type t
-  use prelude.Borrow
-  predicate resolve (self : borrowed t)
-  val resolve (self : borrowed t) : bool
-    ensures { result = resolve self }
-    
-end
-module CreusotContracts_Resolve_Impl1_Resolve
-  type t
-  use prelude.Borrow
-  predicate resolve (self : borrowed t) =
-    [#"../../../../../creusot-contracts/src/resolve.rs" 25 20 25 34]  ^ self =  * self
-  val resolve (self : borrowed t) : bool
-    ensures { result = resolve self }
-    
 end
 module CreusotContracts_Model_ShallowModel_ShallowModelTy_Type
   type self
@@ -241,10 +219,8 @@ module C02IterMut_Impl1_Completed
     type t = slice t,
     type ShallowModelTy0.shallowModelTy = Seq.seq t
   use C02IterMut_IterMut_Type as C02IterMut_IterMut_Type
-  clone CreusotContracts_Resolve_Impl1_Resolve_Stub as Resolve0 with
-    type t = C02IterMut_IterMut_Type.t_itermut t
   predicate completed [#"../02_iter_mut.rs" 31 4 31 35] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) =
-    [#"../02_iter_mut.rs" 32 8 32 70] Resolve0.resolve self /\ Seq.(==) (ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner ( * self))) (Seq.empty )
+    [#"../02_iter_mut.rs" 32 8 32 88] ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner ( * self)) = ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner ( ^ self)) /\ Seq.(==) (ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner ( * self))) (Seq.empty )
   val completed [#"../02_iter_mut.rs" 31 4 31 35] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) : bool
     ensures { result = completed self }
     
@@ -382,17 +358,18 @@ module C02IterMut_Impl1_Produces
   type t
   use seq.Seq
   use prelude.Borrow
+  use prelude.Int
   use prelude.Slice
   use seq.Seq
   clone CreusotContracts_Invariant_Inv_Stub as Inv1 with
     type t = Seq.seq (borrowed t)
   clone CreusotContracts_Logic_Ops_Impl2_IndexLogic_Stub as IndexLogic0 with
     type t = t
+  clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
+    type t = borrowed (slice t)
   clone CreusotContracts_Model_Impl7_ShallowModel_Stub as ShallowModel0 with
     type t = slice t,
     type ShallowModelTy0.shallowModelTy = Seq.seq t
-  clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
-    type t = borrowed (slice t)
   clone CreusotContracts_Std1_Slice_Impl4_ToMutSeq_Stub as ToMutSeq0 with
     type t = t,
     predicate Inv0.inv = Inv0.inv,
@@ -404,7 +381,7 @@ module C02IterMut_Impl1_Produces
   predicate produces [#"../02_iter_mut.rs" 37 4 37 65] (self : C02IterMut_IterMut_Type.t_itermut t) (visited : Seq.seq (borrowed t)) (tl : C02IterMut_IterMut_Type.t_itermut t)
     
    =
-    [#"../02_iter_mut.rs" 36 4 36 16] Seq.(==) (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner self)) (Seq.(++) visited (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner tl)))
+    [#"../02_iter_mut.rs" 39 12 43 13] Seq.length (ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner self)) = Seq.length visited + Seq.length (ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner tl)) /\ (forall i : int . 0 <= i /\ i < Seq.length (ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner self)) ->  * Seq.get (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner self)) i =  * Seq.get (Seq.(++) visited (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner tl))) i /\  ^ Seq.get (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner self)) i =  ^ Seq.get (Seq.(++) visited (ToMutSeq0.to_mut_seq (C02IterMut_IterMut_Type.itermut_inner tl))) i)
   val produces [#"../02_iter_mut.rs" 37 4 37 65] (self : C02IterMut_IterMut_Type.t_itermut t) (visited : Seq.seq (borrowed t)) (tl : C02IterMut_IterMut_Type.t_itermut t) : bool
     ensures { result = produces self visited tl }
     
@@ -438,7 +415,7 @@ module C02IterMut_Impl1_ProducesRefl_Stub
     type t = t
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C02IterMut_IterMut_Type.t_itermut t
-  function produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
+  function produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
 end
 module C02IterMut_Impl1_ProducesRefl_Interface
   type t
@@ -448,13 +425,13 @@ module C02IterMut_Impl1_ProducesRefl_Interface
     type t = t
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C02IterMut_IterMut_Type.t_itermut t
-  function produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
-  val produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 44 21 44 22] Inv0.inv a}
-    ensures { [#"../02_iter_mut.rs" 43 14 43 39] Produces0.produces a (Seq.empty ) a }
+  function produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
+  val produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 50 21 50 22] Inv0.inv a}
+    ensures { [#"../02_iter_mut.rs" 49 14 49 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 44 21 44 22] Inv0.inv a) -> ([#"../02_iter_mut.rs" 43 14 43 39] Produces0.produces a (Seq.empty ) a)
+  axiom produces_refl_spec : forall a : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 50 21 50 22] Inv0.inv a) -> ([#"../02_iter_mut.rs" 49 14 49 39] Produces0.produces a (Seq.empty ) a)
 end
 module C02IterMut_Impl1_ProducesRefl
   type t
@@ -464,14 +441,14 @@ module C02IterMut_Impl1_ProducesRefl
     type t = t
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C02IterMut_IterMut_Type.t_itermut t
-  function produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : () =
-    [#"../02_iter_mut.rs" 41 4 41 10] ()
-  val produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 44 21 44 22] Inv0.inv a}
-    ensures { [#"../02_iter_mut.rs" 43 14 43 39] Produces0.produces a (Seq.empty ) a }
+  function produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : () =
+    [#"../02_iter_mut.rs" 47 4 47 10] ()
+  val produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 50 21 50 22] Inv0.inv a}
+    ensures { [#"../02_iter_mut.rs" 49 14 49 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 44 21 44 22] Inv0.inv a) -> ([#"../02_iter_mut.rs" 43 14 43 39] Produces0.produces a (Seq.empty ) a)
+  axiom produces_refl_spec : forall a : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 50 21 50 22] Inv0.inv a) -> ([#"../02_iter_mut.rs" 49 14 49 39] Produces0.produces a (Seq.empty ) a)
 end
 module C02IterMut_Impl1_ProducesRefl_Impl
   type t
@@ -504,18 +481,18 @@ module C02IterMut_Impl1_ProducesRefl_Impl
     predicate Inv0.inv = Inv2.inv,
     axiom .
   clone Core_Num_Impl11_Max as Max0
-  clone CreusotContracts_Std1_Slice_Impl0_ShallowModel_Interface as ShallowModel1 with
-    type t = t,
-    predicate Inv0.inv = Inv4.inv,
-    val Max0.mAX' = Max0.mAX',
-    predicate Inv1.inv = Inv5.inv,
-    axiom .
   clone CreusotContracts_Invariant_Inv_Interface as Inv1 with
     type t = borrowed (slice t)
   clone TyInv_Trivial as TyInv_Trivial0 with
     type t = borrowed (slice t),
     predicate Inv0.inv = Inv1.inv,
     axiom .
+  clone CreusotContracts_Std1_Slice_Impl0_ShallowModel_Interface as ShallowModel1 with
+    type t = t,
+    predicate Inv0.inv = Inv4.inv,
+    val Max0.mAX' = Max0.mAX',
+    predicate Inv1.inv = Inv5.inv,
+    axiom .
   use C02IterMut_IterMut_Type as C02IterMut_IterMut_Type
   clone C02IterMut_Impl0_Invariant as Invariant0 with
     type t = t,
@@ -550,17 +527,17 @@ module C02IterMut_Impl1_ProducesRefl_Impl
     axiom .
   clone C02IterMut_Impl1_Produces as Produces0 with
     type t = t,
+    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function ToMutSeq0.to_mut_seq = ToMutSeq0.to_mut_seq,
     predicate Inv0.inv = Inv1.inv,
-    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function IndexLogic0.index_logic = IndexLogic0.index_logic,
     predicate Inv1.inv = Inv2.inv
-  let rec ghost function produces_refl [#"../02_iter_mut.rs" 44 4 44 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 44 21 44 22] Inv0.inv a}
-    ensures { [#"../02_iter_mut.rs" 43 14 43 39] Produces0.produces a (Seq.empty ) a }
+  let rec ghost function produces_refl [#"../02_iter_mut.rs" 50 4 50 29] (a : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 50 21 50 22] Inv0.inv a}
+    ensures { [#"../02_iter_mut.rs" 49 14 49 39] Produces0.produces a (Seq.empty ) a }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
-    [#"../02_iter_mut.rs" 41 4 41 10] ()
+    [#"../02_iter_mut.rs" 47 4 47 10] ()
 end
 module C02IterMut_Impl1_ProducesTrans_Stub
   type t
@@ -574,7 +551,7 @@ module C02IterMut_Impl1_ProducesTrans_Stub
     type t = C02IterMut_IterMut_Type.t_itermut t
   clone C02IterMut_Impl1_Produces_Stub as Produces0 with
     type t = t
-  function produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+  function produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
     
 end
 module C02IterMut_Impl1_ProducesTrans_Interface
@@ -589,20 +566,20 @@ module C02IterMut_Impl1_ProducesTrans_Interface
     type t = C02IterMut_IterMut_Type.t_itermut t
   clone C02IterMut_Impl1_Produces_Stub as Produces0 with
     type t = t
-  function produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
-    
-  val produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 48 15 48 32] Produces0.produces a ab b}
-    requires {[#"../02_iter_mut.rs" 49 15 49 32] Produces0.produces b bc c}
-    requires {[#"../02_iter_mut.rs" 51 22 51 23] Inv0.inv a}
-    requires {[#"../02_iter_mut.rs" 51 31 51 33] Inv1.inv ab}
-    requires {[#"../02_iter_mut.rs" 51 52 51 53] Inv0.inv b}
-    requires {[#"../02_iter_mut.rs" 51 61 51 63] Inv1.inv bc}
-    requires {[#"../02_iter_mut.rs" 51 82 51 83] Inv0.inv c}
-    ensures { [#"../02_iter_mut.rs" 50 14 50 42] Produces0.produces a (Seq.(++) ab bc) c }
+  function produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+    
+  val produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 54 15 54 32] Produces0.produces a ab b}
+    requires {[#"../02_iter_mut.rs" 55 15 55 32] Produces0.produces b bc c}
+    requires {[#"../02_iter_mut.rs" 57 22 57 23] Inv0.inv a}
+    requires {[#"../02_iter_mut.rs" 57 31 57 33] Inv1.inv ab}
+    requires {[#"../02_iter_mut.rs" 57 52 57 53] Inv0.inv b}
+    requires {[#"../02_iter_mut.rs" 57 61 57 63] Inv1.inv bc}
+    requires {[#"../02_iter_mut.rs" 57 82 57 83] Inv0.inv c}
+    ensures { [#"../02_iter_mut.rs" 56 14 56 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : C02IterMut_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : C02IterMut_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 48 15 48 32] Produces0.produces a ab b) -> ([#"../02_iter_mut.rs" 49 15 49 32] Produces0.produces b bc c) -> ([#"../02_iter_mut.rs" 51 22 51 23] Inv0.inv a) -> ([#"../02_iter_mut.rs" 51 31 51 33] Inv1.inv ab) -> ([#"../02_iter_mut.rs" 51 52 51 53] Inv0.inv b) -> ([#"../02_iter_mut.rs" 51 61 51 63] Inv1.inv bc) -> ([#"../02_iter_mut.rs" 51 82 51 83] Inv0.inv c) -> ([#"../02_iter_mut.rs" 50 14 50 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : C02IterMut_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : C02IterMut_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 54 15 54 32] Produces0.produces a ab b) -> ([#"../02_iter_mut.rs" 55 15 55 32] Produces0.produces b bc c) -> ([#"../02_iter_mut.rs" 57 22 57 23] Inv0.inv a) -> ([#"../02_iter_mut.rs" 57 31 57 33] Inv1.inv ab) -> ([#"../02_iter_mut.rs" 57 52 57 53] Inv0.inv b) -> ([#"../02_iter_mut.rs" 57 61 57 63] Inv1.inv bc) -> ([#"../02_iter_mut.rs" 57 82 57 83] Inv0.inv c) -> ([#"../02_iter_mut.rs" 56 14 56 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module C02IterMut_Impl1_ProducesTrans
   type t
@@ -616,22 +593,22 @@ module C02IterMut_Impl1_ProducesTrans
     type t = C02IterMut_IterMut_Type.t_itermut t
   clone C02IterMut_Impl1_Produces_Stub as Produces0 with
     type t = t
-  function produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+  function produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
     
    =
-    [#"../02_iter_mut.rs" 46 4 46 10] ()
-  val produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 48 15 48 32] Produces0.produces a ab b}
-    requires {[#"../02_iter_mut.rs" 49 15 49 32] Produces0.produces b bc c}
-    requires {[#"../02_iter_mut.rs" 51 22 51 23] Inv0.inv a}
-    requires {[#"../02_iter_mut.rs" 51 31 51 33] Inv1.inv ab}
-    requires {[#"../02_iter_mut.rs" 51 52 51 53] Inv0.inv b}
-    requires {[#"../02_iter_mut.rs" 51 61 51 63] Inv1.inv bc}
-    requires {[#"../02_iter_mut.rs" 51 82 51 83] Inv0.inv c}
-    ensures { [#"../02_iter_mut.rs" 50 14 50 42] Produces0.produces a (Seq.(++) ab bc) c }
+    [#"../02_iter_mut.rs" 52 4 52 10] ()
+  val produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 54 15 54 32] Produces0.produces a ab b}
+    requires {[#"../02_iter_mut.rs" 55 15 55 32] Produces0.produces b bc c}
+    requires {[#"../02_iter_mut.rs" 57 22 57 23] Inv0.inv a}
+    requires {[#"../02_iter_mut.rs" 57 31 57 33] Inv1.inv ab}
+    requires {[#"../02_iter_mut.rs" 57 52 57 53] Inv0.inv b}
+    requires {[#"../02_iter_mut.rs" 57 61 57 63] Inv1.inv bc}
+    requires {[#"../02_iter_mut.rs" 57 82 57 83] Inv0.inv c}
+    ensures { [#"../02_iter_mut.rs" 56 14 56 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : C02IterMut_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : C02IterMut_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 48 15 48 32] Produces0.produces a ab b) -> ([#"../02_iter_mut.rs" 49 15 49 32] Produces0.produces b bc c) -> ([#"../02_iter_mut.rs" 51 22 51 23] Inv0.inv a) -> ([#"../02_iter_mut.rs" 51 31 51 33] Inv1.inv ab) -> ([#"../02_iter_mut.rs" 51 52 51 53] Inv0.inv b) -> ([#"../02_iter_mut.rs" 51 61 51 63] Inv1.inv bc) -> ([#"../02_iter_mut.rs" 51 82 51 83] Inv0.inv c) -> ([#"../02_iter_mut.rs" 50 14 50 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : C02IterMut_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : C02IterMut_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : C02IterMut_IterMut_Type.t_itermut t . ([#"../02_iter_mut.rs" 54 15 54 32] Produces0.produces a ab b) -> ([#"../02_iter_mut.rs" 55 15 55 32] Produces0.produces b bc c) -> ([#"../02_iter_mut.rs" 57 22 57 23] Inv0.inv a) -> ([#"../02_iter_mut.rs" 57 31 57 33] Inv1.inv ab) -> ([#"../02_iter_mut.rs" 57 52 57 53] Inv0.inv b) -> ([#"../02_iter_mut.rs" 57 61 57 63] Inv1.inv bc) -> ([#"../02_iter_mut.rs" 57 82 57 83] Inv0.inv c) -> ([#"../02_iter_mut.rs" 56 14 56 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module C02IterMut_Impl1_ProducesTrans_Impl
   type t
@@ -710,23 +687,23 @@ module C02IterMut_Impl1_ProducesTrans_Impl
     axiom .
   clone C02IterMut_Impl1_Produces as Produces0 with
     type t = t,
+    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function ToMutSeq0.to_mut_seq = ToMutSeq0.to_mut_seq,
     predicate Inv0.inv = Inv2.inv,
-    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function IndexLogic0.index_logic = IndexLogic0.index_logic,
     predicate Inv1.inv = Inv1.inv
-  let rec ghost function produces_trans [#"../02_iter_mut.rs" 51 4 51 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
-    requires {[#"../02_iter_mut.rs" 48 15 48 32] Produces0.produces a ab b}
-    requires {[#"../02_iter_mut.rs" 49 15 49 32] Produces0.produces b bc c}
-    requires {[#"../02_iter_mut.rs" 51 22 51 23] Inv0.inv a}
-    requires {[#"../02_iter_mut.rs" 51 31 51 33] Inv1.inv ab}
-    requires {[#"../02_iter_mut.rs" 51 52 51 53] Inv0.inv b}
-    requires {[#"../02_iter_mut.rs" 51 61 51 63] Inv1.inv bc}
-    requires {[#"../02_iter_mut.rs" 51 82 51 83] Inv0.inv c}
-    ensures { [#"../02_iter_mut.rs" 50 14 50 42] Produces0.produces a (Seq.(++) ab bc) c }
+  let rec ghost function produces_trans [#"../02_iter_mut.rs" 57 4 57 90] (a : C02IterMut_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : C02IterMut_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : C02IterMut_IterMut_Type.t_itermut t) : ()
+    requires {[#"../02_iter_mut.rs" 54 15 54 32] Produces0.produces a ab b}
+    requires {[#"../02_iter_mut.rs" 55 15 55 32] Produces0.produces b bc c}
+    requires {[#"../02_iter_mut.rs" 57 22 57 23] Inv0.inv a}
+    requires {[#"../02_iter_mut.rs" 57 31 57 33] Inv1.inv ab}
+    requires {[#"../02_iter_mut.rs" 57 52 57 53] Inv0.inv b}
+    requires {[#"../02_iter_mut.rs" 57 61 57 63] Inv1.inv bc}
+    requires {[#"../02_iter_mut.rs" 57 82 57 83] Inv0.inv c}
+    ensures { [#"../02_iter_mut.rs" 56 14 56 42] Produces0.produces a (Seq.(++) ab bc) c }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
-    [#"../02_iter_mut.rs" 46 4 46 10] ()
+    [#"../02_iter_mut.rs" 52 4 52 10] ()
 end
 module Core_Option_Option_Type
   type t_option 't =
@@ -739,6 +716,28 @@ module Core_Option_Option_Type
       | C_Some a -> a
       end
 end
+module CreusotContracts_Resolve_Impl1_Resolve_Stub
+  type t
+  use prelude.Borrow
+  predicate resolve (self : borrowed t)
+end
+module CreusotContracts_Resolve_Impl1_Resolve_Interface
+  type t
+  use prelude.Borrow
+  predicate resolve (self : borrowed t)
+  val resolve (self : borrowed t) : bool
+    ensures { result = resolve self }
+    
+end
+module CreusotContracts_Resolve_Impl1_Resolve
+  type t
+  use prelude.Borrow
+  predicate resolve (self : borrowed t) =
+    [#"../../../../../creusot-contracts/src/resolve.rs" 25 20 25 34]  ^ self =  * self
+  val resolve (self : borrowed t) : bool
+    ensures { result = resolve self }
+    
+end
 module CreusotContracts_Logic_Seq_Impl0_Tail_Stub
   type t
   use seq.Seq
@@ -793,7 +792,7 @@ module Core_Slice_Impl0_TakeFirstMut_Interface
     requires {Inv0.inv self}
     ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 271 18 278 9] match (result) with
       | Core_Option_Option_Type.C_Some r ->  * r = IndexLogic0.index_logic ( *  * self) 0 /\  ^ r = IndexLogic0.index_logic ( ^  * self) 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self)) > 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self)) > 0 /\ ShallowModel0.shallow_model ( *  ^ self) = Tail0.tail (ShallowModel0.shallow_model ( *  * self)) /\ ShallowModel0.shallow_model ( ^  ^ self) = Tail0.tail (ShallowModel0.shallow_model ( ^  * self))
-      | Core_Option_Option_Type.C_None ->  ^ self =  * self /\ Seq.length (ShallowModel0.shallow_model ( *  * self)) = 0
+      | Core_Option_Option_Type.C_None -> Seq.length (ShallowModel0.shallow_model ( *  ^ self)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  ^ self)) = 0
       end }
     ensures { Inv1.inv result }
     
@@ -821,13 +820,13 @@ module C02IterMut_Impl1_Next_Interface
     type t = t
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = borrowed (C02IterMut_IterMut_Type.t_itermut t)
-  val next [#"../02_iter_mut.rs" 57 4 57 44] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) : Core_Option_Option_Type.t_option (borrowed t)
-    requires {[#"../02_iter_mut.rs" 57 17 57 21] Inv0.inv self}
-    ensures { [#"../02_iter_mut.rs" 53 14 56 5] match (result) with
+  val next [#"../02_iter_mut.rs" 63 4 63 44] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) : Core_Option_Option_Type.t_option (borrowed t)
+    requires {[#"../02_iter_mut.rs" 63 17 63 21] Inv0.inv self}
+    ensures { [#"../02_iter_mut.rs" 59 14 62 5] match (result) with
       | Core_Option_Option_Type.C_None -> Completed0.completed self
       | Core_Option_Option_Type.C_Some v -> Produces0.produces ( * self) (Seq.singleton v) ( ^ self)
       end }
-    ensures { [#"../02_iter_mut.rs" 57 26 57 44] Inv1.inv result }
+    ensures { [#"../02_iter_mut.rs" 63 26 63 44] Inv1.inv result }
     
 end
 module C02IterMut_Impl1_Next
@@ -929,17 +928,16 @@ module C02IterMut_Impl1_Next
     axiom .
   clone C02IterMut_Impl1_Produces as Produces0 with
     type t = t,
+    function ShallowModel0.shallow_model = ShallowModel1.shallow_model,
     function ToMutSeq0.to_mut_seq = ToMutSeq0.to_mut_seq,
     predicate Inv0.inv = Inv0.inv,
-    function ShallowModel0.shallow_model = ShallowModel1.shallow_model,
     function IndexLogic0.index_logic = IndexLogic0.index_logic,
     predicate Inv1.inv = Inv6.inv
-  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve0 with
-    type t = C02IterMut_IterMut_Type.t_itermut t
   clone C02IterMut_Impl1_Completed as Completed0 with
     type t = t,
-    predicate Resolve0.resolve = Resolve0.resolve,
     function ShallowModel0.shallow_model = ShallowModel1.shallow_model
+  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve0 with
+    type t = C02IterMut_IterMut_Type.t_itermut t
   clone Core_Slice_Impl0_TakeFirstMut_Interface as TakeFirstMut0 with
     type t = t,
     predicate Inv0.inv = Inv3.inv,
@@ -950,13 +948,13 @@ module C02IterMut_Impl1_Next
     predicate Inv2.inv = Inv4.inv,
     val Max0.mAX' = Max0.mAX',
     predicate Inv3.inv = Inv5.inv
-  let rec cfg next [#"../02_iter_mut.rs" 57 4 57 44] [@cfg:stackify] [@cfg:subregion_analysis] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) : Core_Option_Option_Type.t_option (borrowed t)
-    requires {[#"../02_iter_mut.rs" 57 17 57 21] Inv1.inv self}
-    ensures { [#"../02_iter_mut.rs" 53 14 56 5] match (result) with
+  let rec cfg next [#"../02_iter_mut.rs" 63 4 63 44] [@cfg:stackify] [@cfg:subregion_analysis] (self : borrowed (C02IterMut_IterMut_Type.t_itermut t)) : Core_Option_Option_Type.t_option (borrowed t)
+    requires {[#"../02_iter_mut.rs" 63 17 63 21] Inv1.inv self}
+    ensures { [#"../02_iter_mut.rs" 59 14 62 5] match (result) with
       | Core_Option_Option_Type.C_None -> Completed0.completed self
       | Core_Option_Option_Type.C_Some v -> Produces0.produces ( * self) (Seq.singleton v) ( ^ self)
       end }
-    ensures { [#"../02_iter_mut.rs" 57 26 57 44] Inv2.inv result }
+    ensures { [#"../02_iter_mut.rs" 63 26 63 44] Inv2.inv result }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : Core_Option_Option_Type.t_option (borrowed t);
@@ -966,10 +964,10 @@ module C02IterMut_Impl1_Next
     goto BB0
   }
   BB0 {
-    _3 <- Borrow.borrow_mut (C02IterMut_IterMut_Type.itermut_inner ( * self));
+    _3 <- Borrow.borrow_final (C02IterMut_IterMut_Type.itermut_inner ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C02IterMut_IterMut_Type.C_IterMut a =  * self in C02IterMut_IterMut_Type.C_IterMut ( ^ _3)) ; };
     assume { Inv0.inv ( ^ _3) };
-    _0 <- ([#"../02_iter_mut.rs" 58 8 58 37] TakeFirstMut0.take_first_mut _3);
+    _0 <- ([#"../02_iter_mut.rs" 64 8 64 37] TakeFirstMut0.take_first_mut _3);
     _3 <- any borrowed (borrowed (slice t));
     goto BB1
   }
@@ -985,10 +983,10 @@ module C02IterMut_Impl2_IntoIter_Interface
   use C02IterMut_IterMut_Type as C02IterMut_IterMut_Type
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C02IterMut_IterMut_Type.t_itermut t
-  val into_iter [#"../02_iter_mut.rs" 64 4 64 30] (self : C02IterMut_IterMut_Type.t_itermut t) : C02IterMut_IterMut_Type.t_itermut t
-    requires {[#"../02_iter_mut.rs" 64 17 64 21] Inv0.inv self}
-    ensures { [#"../02_iter_mut.rs" 63 14 63 28] result = self }
-    ensures { [#"../02_iter_mut.rs" 64 26 64 30] Inv0.inv result }
+  val into_iter [#"../02_iter_mut.rs" 70 4 70 30] (self : C02IterMut_IterMut_Type.t_itermut t) : C02IterMut_IterMut_Type.t_itermut t
+    requires {[#"../02_iter_mut.rs" 70 17 70 21] Inv0.inv self}
+    ensures { [#"../02_iter_mut.rs" 69 14 69 28] result = self }
+    ensures { [#"../02_iter_mut.rs" 70 26 70 30] Inv0.inv result }
     
 end
 module C02IterMut_Impl2_IntoIter
@@ -1036,10 +1034,10 @@ module C02IterMut_Impl2_IntoIter
     predicate Invariant0.invariant' = Invariant0.invariant',
     predicate Inv1.inv = Inv1.inv,
     axiom .
-  let rec cfg into_iter [#"../02_iter_mut.rs" 64 4 64 30] [@cfg:stackify] [@cfg:subregion_analysis] (self : C02IterMut_IterMut_Type.t_itermut t) : C02IterMut_IterMut_Type.t_itermut t
-    requires {[#"../02_iter_mut.rs" 64 17 64 21] Inv0.inv self}
-    ensures { [#"../02_iter_mut.rs" 63 14 63 28] result = self }
-    ensures { [#"../02_iter_mut.rs" 64 26 64 30] Inv0.inv result }
+  let rec cfg into_iter [#"../02_iter_mut.rs" 70 4 70 30] [@cfg:stackify] [@cfg:subregion_analysis] (self : C02IterMut_IterMut_Type.t_itermut t) : C02IterMut_IterMut_Type.t_itermut t
+    requires {[#"../02_iter_mut.rs" 70 17 70 21] Inv0.inv self}
+    ensures { [#"../02_iter_mut.rs" 69 14 69 28] result = self }
+    ensures { [#"../02_iter_mut.rs" 70 26 70 30] Inv0.inv result }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : C02IterMut_IterMut_Type.t_itermut t;
@@ -1441,12 +1439,12 @@ module C02IterMut_IterMut_Interface
     type ShallowModelTy0.shallowModelTy = Seq.seq t
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global))
-  val iter_mut [#"../02_iter_mut.rs" 72 0 72 55] (v : borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global))) : C02IterMut_IterMut_Type.t_itermut t
-    requires {[#"../02_iter_mut.rs" 72 19 72 20] Inv0.inv v}
-    ensures { [#"../02_iter_mut.rs" 69 10 69 29] ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel1.shallow_model v }
-    ensures { [#"../02_iter_mut.rs" 70 10 70 35] ShallowModel2.shallow_model ( ^ C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel3.shallow_model ( ^ v) }
-    ensures { [#"../02_iter_mut.rs" 71 10 71 33] Seq.length (ShallowModel3.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
-    ensures { [#"../02_iter_mut.rs" 72 41 72 55] Inv1.inv result }
+  val iter_mut [#"../02_iter_mut.rs" 78 0 78 55] (v : borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global))) : C02IterMut_IterMut_Type.t_itermut t
+    requires {[#"../02_iter_mut.rs" 78 19 78 20] Inv0.inv v}
+    ensures { [#"../02_iter_mut.rs" 75 10 75 29] ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel1.shallow_model v }
+    ensures { [#"../02_iter_mut.rs" 76 10 76 35] ShallowModel2.shallow_model ( ^ C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel3.shallow_model ( ^ v) }
+    ensures { [#"../02_iter_mut.rs" 77 10 77 33] Seq.length (ShallowModel3.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
+    ensures { [#"../02_iter_mut.rs" 78 41 78 55] Inv1.inv result }
     
 end
 module C02IterMut_IterMut
@@ -1567,12 +1565,12 @@ module C02IterMut_IterMut
     predicate Inv3.inv = Inv0.inv,
     val Max0.mAX' = Max0.mAX',
     predicate Inv4.inv = Inv6.inv
-  let rec cfg iter_mut [#"../02_iter_mut.rs" 72 0 72 55] [@cfg:stackify] [@cfg:subregion_analysis] (v : borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global))) : C02IterMut_IterMut_Type.t_itermut t
-    requires {[#"../02_iter_mut.rs" 72 19 72 20] Inv3.inv v}
-    ensures { [#"../02_iter_mut.rs" 69 10 69 29] ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel1.shallow_model v }
-    ensures { [#"../02_iter_mut.rs" 70 10 70 35] ShallowModel2.shallow_model ( ^ C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel3.shallow_model ( ^ v) }
-    ensures { [#"../02_iter_mut.rs" 71 10 71 33] Seq.length (ShallowModel3.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
-    ensures { [#"../02_iter_mut.rs" 72 41 72 55] Inv4.inv result }
+  let rec cfg iter_mut [#"../02_iter_mut.rs" 78 0 78 55] [@cfg:stackify] [@cfg:subregion_analysis] (v : borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global))) : C02IterMut_IterMut_Type.t_itermut t
+    requires {[#"../02_iter_mut.rs" 78 19 78 20] Inv3.inv v}
+    ensures { [#"../02_iter_mut.rs" 75 10 75 29] ShallowModel0.shallow_model (C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel1.shallow_model v }
+    ensures { [#"../02_iter_mut.rs" 76 10 76 35] ShallowModel2.shallow_model ( ^ C02IterMut_IterMut_Type.itermut_inner result) = ShallowModel3.shallow_model ( ^ v) }
+    ensures { [#"../02_iter_mut.rs" 77 10 77 33] Seq.length (ShallowModel3.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
+    ensures { [#"../02_iter_mut.rs" 78 41 78 55] Inv4.inv result }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : C02IterMut_IterMut_Type.t_itermut t;
@@ -1585,18 +1583,18 @@ module C02IterMut_IterMut
     goto BB0
   }
   BB0 {
-    _8 <- Borrow.borrow_mut ( * v);
+    _8 <- Borrow.borrow_final ( * v) (Borrow.get_id v);
     v <- { v with current = ( ^ _8) ; };
     assume { Inv0.inv ( ^ _8) };
-    _7 <- ([#"../02_iter_mut.rs" 73 26 73 31] IndexMut0.index_mut _8 (Core_Ops_Range_RangeFull_Type.C_RangeFull));
+    _7 <- ([#"../02_iter_mut.rs" 79 26 79 31] IndexMut0.index_mut _8 (Core_Ops_Range_RangeFull_Type.C_RangeFull));
     _8 <- any borrowed (Alloc_Vec_Vec_Type.t_vec t (Alloc_Alloc_Global_Type.t_global));
     goto BB1
   }
   BB1 {
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     assume { Inv1.inv ( ^ _6) };
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     assume { Inv1.inv ( ^ _5) };
     _0 <- C02IterMut_IterMut_Type.C_IterMut _5;
@@ -1707,9 +1705,9 @@ module C02IterMut_AllZero_Interface
     val Max0.mAX' = Max0.mAX',
     predicate Inv1.inv = Inv1.inv,
     axiom .
-  val all_zero [#"../02_iter_mut.rs" 78 0 78 35] (v : borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global))) : ()
-    ensures { [#"../02_iter_mut.rs" 76 10 76 33] Seq.length (ShallowModel0.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
-    ensures { [#"../02_iter_mut.rs" 77 0 77 66] forall i : int . 0 <= i /\ i < Seq.length (ShallowModel1.shallow_model v) -> UIntSize.to_int (IndexLogic0.index_logic ( ^ v) i) = 0 }
+  val all_zero [#"../02_iter_mut.rs" 84 0 84 35] (v : borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global))) : ()
+    ensures { [#"../02_iter_mut.rs" 82 10 82 33] Seq.length (ShallowModel0.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
+    ensures { [#"../02_iter_mut.rs" 83 0 83 66] forall i : int . 0 <= i /\ i < Seq.length (ShallowModel1.shallow_model v) -> UIntSize.to_int (IndexLogic0.index_logic ( ^ v) i) = 0 }
     
 end
 module C02IterMut_AllZero
@@ -1733,8 +1731,6 @@ module C02IterMut_AllZero
     predicate Inv0.inv = Inv8.inv,
     axiom .
   use C02IterMut_IterMut_Type as C02IterMut_IterMut_Type
-  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve2 with
-    type t = C02IterMut_IterMut_Type.t_itermut usize
   clone CreusotContracts_Invariant_Inv_Interface as Inv0 with
     type t = C02IterMut_IterMut_Type.t_itermut usize
   clone CreusotContracts_Invariant_Inv_Interface as Inv7 with
@@ -1802,7 +1798,6 @@ module C02IterMut_AllZero
     function ShallowModel0.shallow_model = ShallowModel3.shallow_model
   clone C02IterMut_Impl1_Completed as Completed0 with
     type t = usize,
-    predicate Resolve0.resolve = Resolve2.resolve,
     function ShallowModel0.shallow_model = ShallowModel2.shallow_model
   clone CreusotContracts_Logic_Ops_Impl2_IndexLogic as IndexLogic2 with
     type t = usize,
@@ -1819,9 +1814,9 @@ module C02IterMut_AllZero
     axiom .
   clone C02IterMut_Impl1_Produces as Produces0 with
     type t = usize,
+    function ShallowModel0.shallow_model = ShallowModel2.shallow_model,
     function ToMutSeq0.to_mut_seq = ToMutSeq0.to_mut_seq,
     predicate Inv0.inv = Inv5.inv,
-    function ShallowModel0.shallow_model = ShallowModel2.shallow_model,
     function IndexLogic0.index_logic = IndexLogic2.index_logic,
     predicate Inv1.inv = Inv6.inv
   clone C02IterMut_Impl1_ProducesTrans as ProducesTrans0 with
@@ -1886,9 +1881,9 @@ module C02IterMut_AllZero
     val Max0.mAX' = Max0.mAX',
     predicate Inv3.inv = Inv3.inv,
     predicate Inv4.inv = Inv4.inv
-  let rec cfg all_zero [#"../02_iter_mut.rs" 78 0 78 35] [@cfg:stackify] [@cfg:subregion_analysis] (v : borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global))) : ()
-    ensures { [#"../02_iter_mut.rs" 76 10 76 33] Seq.length (ShallowModel0.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
-    ensures { [#"../02_iter_mut.rs" 77 0 77 66] forall i : int . 0 <= i /\ i < Seq.length (ShallowModel1.shallow_model v) -> UIntSize.to_int (IndexLogic1.index_logic ( ^ v) i) = 0 }
+  let rec cfg all_zero [#"../02_iter_mut.rs" 84 0 84 35] [@cfg:stackify] [@cfg:subregion_analysis] (v : borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global))) : ()
+    ensures { [#"../02_iter_mut.rs" 82 10 82 33] Seq.length (ShallowModel0.shallow_model ( ^ v)) = Seq.length (ShallowModel1.shallow_model v) }
+    ensures { [#"../02_iter_mut.rs" 83 0 83 66] forall i : int . 0 <= i /\ i < Seq.length (ShallowModel1.shallow_model v) -> UIntSize.to_int (IndexLogic1.index_logic ( ^ v) i) = 0 }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : ();
@@ -1906,39 +1901,39 @@ module C02IterMut_AllZero
     goto BB0
   }
   BB0 {
-    _6 <- Borrow.borrow_mut ( * v);
+    _6 <- Borrow.borrow_final ( * v) (Borrow.get_id v);
     v <- { v with current = ( ^ _6) ; };
-    _5 <- ([#"../02_iter_mut.rs" 79 17 79 28] IterMut0.iter_mut _6);
+    _5 <- ([#"../02_iter_mut.rs" 85 17 85 28] IterMut0.iter_mut _6);
     _6 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
     goto BB1
   }
   BB1 {
-    it <- ([#"../02_iter_mut.rs" 79 17 79 40] IntoIter0.into_iter _5);
+    it <- ([#"../02_iter_mut.rs" 85 17 85 40] IntoIter0.into_iter _5);
     _5 <- any C02IterMut_IterMut_Type.t_itermut usize;
     goto BB2
   }
   BB2 {
-    iter_old <- ([#"../02_iter_mut.rs" 80 19 80 29] Ghost.new it);
+    iter_old <- ([#"../02_iter_mut.rs" 86 19 86 29] Ghost.new it);
     goto BB3
   }
   BB3 {
-    produced <- ([#"../02_iter_mut.rs" 81 23 81 41] Ghost.new (Seq.empty ));
+    produced <- ([#"../02_iter_mut.rs" 87 23 87 41] Ghost.new (Seq.empty ));
     goto BB4
   }
   BB4 {
     goto BB5
   }
   BB5 {
-    invariant { [#"../02_iter_mut.rs" 82 16 82 23] Inv0.inv it };
-    invariant { [#"../02_iter_mut.rs" 83 16 83 55] Produces0.produces (Ghost.inner iter_old) (Ghost.inner produced) it };
-    invariant { [#"../02_iter_mut.rs" 82 4 82 25] forall i : int . 0 <= i /\ i < Seq.length (Ghost.inner produced) -> UIntSize.to_int ( ^ IndexLogic0.index_logic produced i) = 0 };
+    invariant { [#"../02_iter_mut.rs" 88 16 88 23] Inv0.inv it };
+    invariant { [#"../02_iter_mut.rs" 89 16 89 55] Produces0.produces (Ghost.inner iter_old) (Ghost.inner produced) it };
+    invariant { [#"../02_iter_mut.rs" 88 4 88 25] forall i : int . 0 <= i /\ i < Seq.length (Ghost.inner produced) -> UIntSize.to_int ( ^ IndexLogic0.index_logic produced i) = 0 };
     goto BB6
   }
   BB6 {
     _16 <- Borrow.borrow_mut it;
     it <-  ^ _16;
     assume { Inv0.inv ( ^ _16) };
-    _15 <- ([#"../02_iter_mut.rs" 86 14 86 23] Next0.next _16);
+    _15 <- ([#"../02_iter_mut.rs" 92 14 92 23] Next0.next _16);
     _16 <- any borrowed (C02IterMut_IterMut_Type.t_itermut usize);
     goto BB7
   }
@@ -1963,13 +1958,13 @@ module C02IterMut_AllZero
   BB11 {
     x <- Core_Option_Option_Type.some_0 _15;
     _15 <- (let Core_Option_Option_Type.C_Some a = _15 in Core_Option_Option_Type.C_Some (any borrowed usize));
-    _19 <- ([#"../02_iter_mut.rs" 88 27 88 69] Ghost.new (Seq.(++) (Ghost.inner produced) (Seq.singleton x)));
+    _19 <- ([#"../02_iter_mut.rs" 94 27 94 69] Ghost.new (Seq.(++) (Ghost.inner produced) (Seq.singleton x)));
     goto BB12
   }
   BB12 {
     produced <- _19;
     _19 <- any Ghost.ghost_ty (Seq.seq (borrowed usize));
-    x <- { x with current = ([#"../02_iter_mut.rs" 89 21 89 22] (0 : usize)) ; };
+    x <- { x with current = ([#"../02_iter_mut.rs" 95 21 95 22] (0 : usize)) ; };
     assume { Resolve0.resolve x };
     goto BB5
   }
@@ -2003,18 +1998,18 @@ module C02IterMut_Impl1
     predicate Inv0.inv = Inv5.inv,
     axiom .
   clone Core_Num_Impl11_Max as Max0
-  clone CreusotContracts_Std1_Slice_Impl0_ShallowModel_Interface as ShallowModel1 with
-    type t = t,
-    predicate Inv0.inv = Inv6.inv,
-    val Max0.mAX' = Max0.mAX',
-    predicate Inv1.inv = Inv7.inv,
-    axiom .
   clone CreusotContracts_Invariant_Inv_Interface as Inv4 with
     type t = borrowed (slice t)
   clone TyInv_Trivial as TyInv_Trivial2 with
     type t = borrowed (slice t),
     predicate Inv0.inv = Inv4.inv,
     axiom .
+  clone CreusotContracts_Std1_Slice_Impl0_ShallowModel_Interface as ShallowModel1 with
+    type t = t,
+    predicate Inv0.inv = Inv6.inv,
+    val Max0.mAX' = Max0.mAX',
+    predicate Inv1.inv = Inv7.inv,
+    axiom .
   use C02IterMut_IterMut_Type as C02IterMut_IterMut_Type
   clone C02IterMut_Impl0_Invariant as Invariant0 with
     type t = t,
@@ -2028,8 +2023,6 @@ module C02IterMut_Impl1
     type t = Seq.seq (borrowed t),
     predicate Inv0.inv = Inv3.inv,
     axiom .
-  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve0 with
-    type t = C02IterMut_IterMut_Type.t_itermut t
   use Core_Option_Option_Type as Core_Option_Option_Type
   clone CreusotContracts_Invariant_Inv_Interface as Inv2 with
     type t = Core_Option_Option_Type.t_option (borrowed t)
@@ -2071,22 +2064,21 @@ module C02IterMut_Impl1
     axiom .
   clone C02IterMut_Impl1_Completed as Completed0 with
     type t = t,
-    predicate Resolve0.resolve = Resolve0.resolve,
     function ShallowModel0.shallow_model = ShallowModel0.shallow_model
   clone C02IterMut_Impl1_Produces as Produces0 with
     type t = t,
+    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function ToMutSeq0.to_mut_seq = ToMutSeq0.to_mut_seq,
     predicate Inv0.inv = Inv4.inv,
-    function ShallowModel0.shallow_model = ShallowModel0.shallow_model,
     function IndexLogic0.index_logic = IndexLogic0.index_logic,
     predicate Inv1.inv = Inv3.inv
-  goal produces_refl_refn : [#"../02_iter_mut.rs" 44 4 44 29] forall a : C02IterMut_IterMut_Type.t_itermut t . Inv0.inv a -> Inv0.inv a /\ (forall result : () . Produces0.produces a (Seq.empty ) a -> Produces0.produces a (Seq.empty ) a)
-  goal next_refn : [#"../02_iter_mut.rs" 57 4 57 44] forall self : borrowed (C02IterMut_IterMut_Type.t_itermut t) . Inv1.inv self -> Inv1.inv self /\ (forall result : Core_Option_Option_Type.t_option (borrowed t) . Inv2.inv result /\ match (result) with
+  goal produces_refl_refn : [#"../02_iter_mut.rs" 50 4 50 29] forall a : C02IterMut_IterMut_Type.t_itermut t . Inv0.inv a -> Inv0.inv a /\ (forall result : () . Produces0.produces a (Seq.empty ) a -> Produces0.produces a (Seq.empty ) a)
+  goal next_refn : [#"../02_iter_mut.rs" 63 4 63 44] forall self : borrowed (C02IterMut_IterMut_Type.t_itermut t) . Inv1.inv self -> Inv1.inv self /\ (forall result : Core_Option_Option_Type.t_option (borrowed t) . Inv2.inv result /\ match (result) with
     | Core_Option_Option_Type.C_None -> Completed0.completed self
     | Core_Option_Option_Type.C_Some v -> Produces0.produces ( * self) (Seq.singleton v) ( ^ self)
     end -> Inv2.inv result /\ match (result) with
     | Core_Option_Option_Type.C_None -> Completed0.completed self
     | Core_Option_Option_Type.C_Some v -> Produces0.produces ( * self) (Seq.singleton v) ( ^ self)
     end)
-  goal produces_trans_refn : [#"../02_iter_mut.rs" 51 4 51 90] forall a : C02IterMut_IterMut_Type.t_itermut t . forall ab : Seq.seq (borrowed t) . forall b : C02IterMut_IterMut_Type.t_itermut t . forall bc : Seq.seq (borrowed t) . forall c : C02IterMut_IterMut_Type.t_itermut t . Inv0.inv c /\ Inv3.inv bc /\ Inv0.inv b /\ Inv3.inv ab /\ Inv0.inv a /\ Produces0.produces b bc c /\ Produces0.produces a ab b -> Inv0.inv c /\ Inv3.inv bc /\ Inv0.inv b /\ Inv3.inv ab /\ Inv0.inv a /\ Produces0.produces b bc c /\ Produces0.produces a ab b /\ (forall result : () . Produces0.produces a (Seq.(++) ab bc) c -> Produces0.produces a (Seq.(++) ab bc) c)
+  goal produces_trans_refn : [#"../02_iter_mut.rs" 57 4 57 90] forall a : C02IterMut_IterMut_Type.t_itermut t . forall ab : Seq.seq (borrowed t) . forall b : C02IterMut_IterMut_Type.t_itermut t . forall bc : Seq.seq (borrowed t) . forall c : C02IterMut_IterMut_Type.t_itermut t . Inv0.inv c /\ Inv3.inv bc /\ Inv0.inv b /\ Inv3.inv ab /\ Inv0.inv a /\ Produces0.produces b bc c /\ Produces0.produces a ab b -> Inv0.inv c /\ Inv3.inv bc /\ Inv0.inv b /\ Inv3.inv ab /\ Inv0.inv a /\ Produces0.produces b bc c /\ Produces0.produces a ab b /\ (forall result : () . Produces0.produces a (Seq.(++) ab bc) c -> Produces0.produces a (Seq.(++) ab bc) c)
 end
diff --git a/creusot/tests/should_succeed/iterators/02_iter_mut.rs b/creusot/tests/should_succeed/iterators/02_iter_mut.rs
index 594dfcfe70..cd7c571076 100644
--- a/creusot/tests/should_succeed/iterators/02_iter_mut.rs
+++ b/creusot/tests/should_succeed/iterators/02_iter_mut.rs
@@ -29,13 +29,19 @@ impl<'a, T> Iterator for IterMut<'a, T> {
     #[open]
     #[predicate]
     fn completed(&mut self) -> bool {
-        pearlite! { self.resolve() && self.inner@.ext_eq(Seq::EMPTY) }
+        pearlite! { (*self).inner@ == (^self).inner@ && self.inner@.ext_eq(Seq::EMPTY) }
     }
 
     #[open]
     #[predicate]
     fn produces(self, visited: Seq<Self::Item>, tl: Self) -> bool {
-        self.inner.to_mut_seq().ext_eq(visited.concat(tl.inner.to_mut_seq()))
+        pearlite! {
+            self.inner@.len() == visited.len() + tl.inner@.len() &&
+            (forall<i:Int> 0 <= i && i < self.inner@.len() ==>
+                *self.inner.to_mut_seq()[i] == *visited.concat(tl.inner.to_mut_seq())[i] &&
+                ^self.inner.to_mut_seq()[i] == ^visited.concat(tl.inner.to_mut_seq())[i]
+            )
+        }
     }
 
     #[law]
diff --git a/creusot/tests/should_succeed/iterators/02_iter_mut/why3session.xml b/creusot/tests/should_succeed/iterators/02_iter_mut/why3session.xml
index ab02f40f50..64a724261b 100644
--- a/creusot/tests/should_succeed/iterators/02_iter_mut/why3session.xml
+++ b/creusot/tests/should_succeed/iterators/02_iter_mut/why3session.xml
@@ -37,7 +37,7 @@
 </theory>
 <theory name="C02IterMut_Impl2_IntoIter" proved="true">
  <goal name="into_iter&#39;vc" expl="VC for into_iter" proved="true">
- <proof prover="4"><result status="valid" time="0.000000" steps="6"/></proof>
+ <proof prover="4"><result status="valid" time="0.008309" steps="6"/></proof>
  </goal>
 </theory>
 <theory name="C02IterMut_IterMut" proved="true">
@@ -89,13 +89,13 @@
 </theory>
 <theory name="C02IterMut_Impl1" proved="true">
  <goal name="produces_refl_refn" proved="true">
- <proof prover="4"><result status="valid" time="0.010000" steps="2"/></proof>
+ <proof prover="4"><result status="valid" time="0.019093" steps="2"/></proof>
  </goal>
  <goal name="next_refn" proved="true">
- <proof prover="4"><result status="valid" time="0.020000" steps="2"/></proof>
+ <proof prover="4"><result status="valid" time="0.021146" steps="2"/></proof>
  </goal>
  <goal name="produces_trans_refn" proved="true">
- <proof prover="4"><result status="valid" time="0.010000" steps="2"/></proof>
+ <proof prover="4"><result status="valid" time="0.007561" steps="2"/></proof>
  </goal>
 </theory>
 </file>
diff --git a/creusot/tests/should_succeed/iterators/03_std_iterators.mlcfg b/creusot/tests/should_succeed/iterators/03_std_iterators.mlcfg
index d30753b61d..b36fa39201 100644
--- a/creusot/tests/should_succeed/iterators/03_std_iterators.mlcfg
+++ b/creusot/tests/should_succeed/iterators/03_std_iterators.mlcfg
@@ -366,7 +366,7 @@ module CreusotContracts_Std1_Slice_Impl14_Produces
   predicate produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t)
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 379 12 379 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 380 12 380 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
   val produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t) : bool
     ensures { result = produces self visited tl }
     
@@ -636,10 +636,10 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl_Interface
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   type t
@@ -648,12 +648,12 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   clone CreusotContracts_Std1_Slice_Impl14_Produces_Stub as Produces0 with
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : () =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 383 4 383 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 384 4 384 10] ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Stub
   type t
@@ -681,14 +681,14 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Interface
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   type t
@@ -703,16 +703,16 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 388 4 388 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 389 4 389 10] ()
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module C03StdIterators_SliceIter_Interface
   type t
@@ -936,7 +936,7 @@ module C03StdIterators_SliceIter
   BB6 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../03_std_iterators.rs" 8 4 8 38] Next0.next _18);
     _18 <- any borrowed (Core_Slice_Iter_Iter_Type.t_iter t);
@@ -1405,7 +1405,7 @@ module C03StdIterators_VecIter
   BB5 {
     _18 <- Borrow.borrow_mut iter;
     iter <-  ^ _18;
-    _17 <- Borrow.borrow_mut ( * _18);
+    _17 <- Borrow.borrow_final ( * _18) (Borrow.get_id _18);
     _18 <- { _18 with current = ( ^ _17) ; };
     _16 <- ([#"../03_std_iterators.rs" 19 4 19 38] Next0.next _17);
     _17 <- any borrowed (Core_Slice_Iter_Iter_Type.t_iter t);
@@ -1548,11 +1548,11 @@ module CreusotContracts_Std1_Slice_Impl15_ShallowModel_Interface
     axiom .
   function shallow_model (self : Core_Slice_Iter_IterMut_Type.t_itermut t) : borrowed (slice t)
   val shallow_model (self : Core_Slice_Iter_IterMut_Type.t_itermut t) : borrowed (slice t)
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 402 14 402 50] Seq.length (ShallowModel0.shallow_model ( ^ result)) = Seq.length (ShallowModel0.shallow_model ( * result)) }
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 403 4 403 50] Inv0.inv result }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 403 14 403 50] Seq.length (ShallowModel0.shallow_model ( ^ result)) = Seq.length (ShallowModel0.shallow_model ( * result)) }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 404 4 404 50] Inv0.inv result }
     ensures { result = shallow_model self }
     
-  axiom shallow_model_spec : forall self : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 403 4 403 50] Inv0.inv (shallow_model self)) && ([#"../../../../../creusot-contracts/src/std/slice.rs" 402 14 402 50] Seq.length (ShallowModel0.shallow_model ( ^ shallow_model self)) = Seq.length (ShallowModel0.shallow_model ( * shallow_model self)))
+  axiom shallow_model_spec : forall self : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 404 4 404 50] Inv0.inv (shallow_model self)) && ([#"../../../../../creusot-contracts/src/std/slice.rs" 403 14 403 50] Seq.length (ShallowModel0.shallow_model ( ^ shallow_model self)) = Seq.length (ShallowModel0.shallow_model ( * shallow_model self)))
 end
 module CreusotContracts_Std1_Slice_Impl15_ShallowModel
   type t
@@ -1576,11 +1576,11 @@ module CreusotContracts_Std1_Slice_Impl15_ShallowModel
     axiom .
   function shallow_model (self : Core_Slice_Iter_IterMut_Type.t_itermut t) : borrowed (slice t)
   val shallow_model (self : Core_Slice_Iter_IterMut_Type.t_itermut t) : borrowed (slice t)
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 402 14 402 50] Seq.length (ShallowModel0.shallow_model ( ^ result)) = Seq.length (ShallowModel0.shallow_model ( * result)) }
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 403 4 403 50] Inv0.inv result }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 403 14 403 50] Seq.length (ShallowModel0.shallow_model ( ^ result)) = Seq.length (ShallowModel0.shallow_model ( * result)) }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 404 4 404 50] Inv0.inv result }
     ensures { result = shallow_model self }
     
-  axiom shallow_model_spec : forall self : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 403 4 403 50] Inv0.inv (shallow_model self)) && ([#"../../../../../creusot-contracts/src/std/slice.rs" 402 14 402 50] Seq.length (ShallowModel0.shallow_model ( ^ shallow_model self)) = Seq.length (ShallowModel0.shallow_model ( * shallow_model self)))
+  axiom shallow_model_spec : forall self : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 404 4 404 50] Inv0.inv (shallow_model self)) && ([#"../../../../../creusot-contracts/src/std/slice.rs" 403 14 403 50] Seq.length (ShallowModel0.shallow_model ( ^ shallow_model self)) = Seq.length (ShallowModel0.shallow_model ( * shallow_model self)))
 end
 module CreusotContracts_Std1_Slice_Impl4_ToMutSeq_Stub
   type t
@@ -1718,7 +1718,7 @@ module CreusotContracts_Std1_Slice_Impl16_Produces
   predicate produces (self : Core_Slice_Iter_IterMut_Type.t_itermut t) (visited : Seq.seq (borrowed t)) (tl : Core_Slice_Iter_IterMut_Type.t_itermut t)
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 428 12 428 66] ToMutSeq0.to_mut_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToMutSeq0.to_mut_seq (ShallowModel0.shallow_model tl))
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 429 12 429 66] ToMutSeq0.to_mut_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToMutSeq0.to_mut_seq (ShallowModel0.shallow_model tl))
   val produces (self : Core_Slice_Iter_IterMut_Type.t_itermut t) (visited : Seq.seq (borrowed t)) (tl : Core_Slice_Iter_IterMut_Type.t_itermut t) : bool
     ensures { result = produces self visited tl }
     
@@ -1793,7 +1793,7 @@ module CreusotContracts_Std1_Slice_Impl17_Resolve
     predicate Inv2.inv = Inv2.inv,
     axiom .
   predicate resolve (self : Core_Slice_Iter_IterMut_Type.t_itermut t) =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 413 20 413 36]  * ShallowModel0.shallow_model self =  ^ ShallowModel0.shallow_model self
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 414 20 414 36]  * ShallowModel0.shallow_model self =  ^ ShallowModel0.shallow_model self
   val resolve (self : Core_Slice_Iter_IterMut_Type.t_itermut t) : bool
     ensures { result = resolve self }
     
@@ -1915,7 +1915,7 @@ module CreusotContracts_Std1_Slice_Impl16_Completed
   clone CreusotContracts_Resolve_Impl1_Resolve_Stub as Resolve0 with
     type t = Core_Slice_Iter_IterMut_Type.t_itermut t
   predicate completed (self : borrowed (Core_Slice_Iter_IterMut_Type.t_itermut t)) =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 421 20 421 61] Resolve0.resolve self /\ ShallowModel1.shallow_model ( * ShallowModel0.shallow_model self) = Seq.empty 
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 422 20 422 61] Resolve0.resolve self /\ ShallowModel1.shallow_model ( * ShallowModel0.shallow_model self) = Seq.empty 
   val completed (self : borrowed (Core_Slice_Iter_IterMut_Type.t_itermut t)) : bool
     ensures { result = completed self }
     
@@ -1956,10 +1956,10 @@ module CreusotContracts_Std1_Slice_Impl16_ProducesRefl_Interface
     type t = t
   function produces_refl (a : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
   val produces_refl (a : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 434 14 434 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 435 14 435 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t . [#"../../../../../creusot-contracts/src/std/slice.rs" 434 14 434 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t . [#"../../../../../creusot-contracts/src/std/slice.rs" 435 14 435 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl16_ProducesRefl
   type t
@@ -1968,12 +1968,12 @@ module CreusotContracts_Std1_Slice_Impl16_ProducesRefl
   clone CreusotContracts_Std1_Slice_Impl16_Produces_Stub as Produces0 with
     type t = t
   function produces_refl (a : Core_Slice_Iter_IterMut_Type.t_itermut t) : () =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 432 4 432 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 433 4 433 10] ()
   val produces_refl (a : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 434 14 434 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 435 14 435 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t . [#"../../../../../creusot-contracts/src/std/slice.rs" 434 14 434 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t . [#"../../../../../creusot-contracts/src/std/slice.rs" 435 14 435 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl16_ProducesTrans_Stub
   type t
@@ -2001,14 +2001,14 @@ module CreusotContracts_Std1_Slice_Impl16_ProducesTrans_Interface
   function produces_trans (a : Core_Slice_Iter_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : Core_Slice_Iter_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
     
   val produces_trans (a : Core_Slice_Iter_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : Core_Slice_Iter_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 439 15 439 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 442 31 442 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 442 61 442 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 441 14 441 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 441 15 441 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 443 31 443 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 443 61 443 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 442 14 442 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : Core_Slice_Iter_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 439 15 439 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 31 442 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 61 442 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 441 14 441 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : Core_Slice_Iter_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 441 15 441 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 443 31 443 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 443 61 443 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 14 442 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module CreusotContracts_Std1_Slice_Impl16_ProducesTrans
   type t
@@ -2023,16 +2023,16 @@ module CreusotContracts_Std1_Slice_Impl16_ProducesTrans
   function produces_trans (a : Core_Slice_Iter_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : Core_Slice_Iter_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 437 4 437 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 438 4 438 10] ()
   val produces_trans (a : Core_Slice_Iter_IterMut_Type.t_itermut t) (ab : Seq.seq (borrowed t)) (b : Core_Slice_Iter_IterMut_Type.t_itermut t) (bc : Seq.seq (borrowed t)) (c : Core_Slice_Iter_IterMut_Type.t_itermut t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 439 15 439 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 442 31 442 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 442 61 442 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 441 14 441 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 441 15 441 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 443 31 443 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 443 61 443 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 442 14 442 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : Core_Slice_Iter_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 439 15 439 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 31 442 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 61 442 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 441 14 441 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_IterMut_Type.t_itermut t, ab : Seq.seq (borrowed t), b : Core_Slice_Iter_IterMut_Type.t_itermut t, bc : Seq.seq (borrowed t), c : Core_Slice_Iter_IterMut_Type.t_itermut t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 440 15 440 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 441 15 441 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 443 31 443 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 443 61 443 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 442 14 442 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module C03StdIterators_AllZero_Interface
   use prelude.Borrow
@@ -2285,14 +2285,14 @@ module C03StdIterators_AllZero
     goto BB0
   }
   BB0 {
-    _8 <- Borrow.borrow_mut ( * v);
+    _8 <- Borrow.borrow_final ( * v) (Borrow.get_id v);
     v <- { v with current = ( ^ _8) ; };
     _7 <- ([#"../03_std_iterators.rs" 30 13 30 25] DerefMut0.deref_mut _8);
     _8 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
     goto BB1
   }
   BB1 {
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     _5 <- ([#"../03_std_iterators.rs" 30 13 30 25] IterMut0.iter_mut _6);
     _6 <- any borrowed (slice usize);
@@ -2324,7 +2324,7 @@ module C03StdIterators_AllZero
   BB7 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../03_std_iterators.rs" 29 4 29 87] Next0.next _18);
     _18 <- any borrowed (Core_Slice_Iter_IterMut_Type.t_itermut usize);
@@ -4197,7 +4197,7 @@ module CreusotContracts_Std1_Iter_MapInv_Impl0_Completed
     type self = i
   use CreusotContracts_Std1_Iter_MapInv_MapInv_Type as CreusotContracts_Std1_Iter_MapInv_MapInv_Type
   predicate completed (self : borrowed (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.t_mapinv i Item0.item f)) =
-    [#"../../../../../creusot-contracts/src/std/iter/map_inv.rs" 15 8 18 9] Ghost.inner (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( * self); final = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( ^ self); addr = Borrow.make_new_addr ()} /\ CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( * self) = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( ^ self)
+    [#"../../../../../creusot-contracts/src/std/iter/map_inv.rs" 15 8 18 9] Ghost.inner (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( * self); final = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1} /\ CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( * self) = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( ^ self)
   val completed (self : borrowed (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.t_mapinv i Item0.item f)) : bool
     ensures { result = completed self }
     
@@ -5268,7 +5268,7 @@ module C03StdIterators_SumRange
   BB5 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../03_std_iterators.rs" 65 4 65 48] Next0.next _18);
     _18 <- any borrowed (Core_Ops_Range_Range_Type.t_range isize);
@@ -5901,7 +5901,7 @@ module C03StdIterators_EnumerateRange
     _14 <- Borrow.borrow_mut iter;
     iter <-  ^ _14;
     assume { Inv0.inv ( ^ _14) };
-    _13 <- Borrow.borrow_mut ( * _14);
+    _13 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _13) ; };
     assume { Inv0.inv ( ^ _13) };
     _12 <- ([#"../03_std_iterators.rs" 73 4 73 96] Next0.next _13);
@@ -6827,7 +6827,7 @@ module C03StdIterators_MyReverse
   BB10 {
     _30 <- Borrow.borrow_mut iter;
     iter <-  ^ _30;
-    _29 <- Borrow.borrow_mut ( * _30);
+    _29 <- Borrow.borrow_final ( * _30) (Borrow.get_id _30);
     _30 <- { _30 with current = ( ^ _29) ; };
     _28 <- ([#"../03_std_iterators.rs" 97 4 97 36] Next0.next _29);
     _29 <- any borrowed (Core_Iter_Adapters_Zip_Zip_Type.t_zip (Core_Ops_Range_Range_Type.t_range usize) (Core_Ops_Range_Range_Type.t_range usize));
diff --git a/creusot/tests/should_succeed/iterators/04_skip.mlcfg b/creusot/tests/should_succeed/iterators/04_skip.mlcfg
index 398967964a..a871cc6a29 100644
--- a/creusot/tests/should_succeed/iterators/04_skip.mlcfg
+++ b/creusot/tests/should_succeed/iterators/04_skip.mlcfg
@@ -893,9 +893,9 @@ module C04Skip_Impl0_Next
   BB1 {
     assert { [@expl:type invariant] Inv0.inv old_self };
     assume { Resolve0.resolve old_self };
-    _7 <- Borrow.borrow_mut (C04Skip_Skip_Type.skip_n ( * self));
+    _7 <- Borrow.borrow_final (C04Skip_Skip_Type.skip_n ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let C04Skip_Skip_Type.C_Skip a b =  * self in C04Skip_Skip_Type.C_Skip a ( ^ _7)) ; };
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     n <- ([#"../04_skip.rs" 65 20 65 47] Take0.take _6);
     _6 <- any borrowed usize;
diff --git a/creusot/tests/should_succeed/iterators/05_map.mlcfg b/creusot/tests/should_succeed/iterators/05_map.mlcfg
index 0f1aeef998..5e2a34b2e3 100644
--- a/creusot/tests/should_succeed/iterators/05_map.mlcfg
+++ b/creusot/tests/should_succeed/iterators/05_map.mlcfg
@@ -61,7 +61,7 @@ module C05Map_Impl0_Completed
     type self = i
   use C05Map_Map_Type as C05Map_Map_Type
   predicate completed [#"../05_map.rs" 22 4 22 35] (self : borrowed (C05Map_Map_Type.t_map i b f)) =
-    [#"../05_map.rs" 23 8 23 75] Completed0.completed {current = C05Map_Map_Type.map_iter ( * self); final = C05Map_Map_Type.map_iter ( ^ self); addr = Borrow.make_new_addr ()} /\ C05Map_Map_Type.map_func ( * self) = C05Map_Map_Type.map_func ( ^ self)
+    [#"../05_map.rs" 23 8 23 75] Completed0.completed {current = C05Map_Map_Type.map_iter ( * self); final = C05Map_Map_Type.map_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1} /\ C05Map_Map_Type.map_func ( * self) = C05Map_Map_Type.map_func ( ^ self)
   val completed [#"../05_map.rs" 22 4 22 35] (self : borrowed (C05Map_Map_Type.t_map i b f)) : bool
     ensures { result = completed self }
     
@@ -2545,7 +2545,7 @@ module C05Map_Impl0_Next
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut (C05Map_Map_Type.map_iter ( * self));
+    _4 <- Borrow.borrow_final (C05Map_Map_Type.map_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C05Map_Map_Type.C_Map a b =  * self in C05Map_Map_Type.C_Map ( ^ _4) b) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../05_map.rs" 61 14 61 30] Next0.next _4);
@@ -2590,7 +2590,7 @@ module C05Map_Impl0_Next
   }
   BB7 {
     assume { Resolve1.resolve _9 };
-    _12 <- Borrow.borrow_mut (C05Map_Map_Type.map_func ( * self));
+    _12 <- Borrow.borrow_final (C05Map_Map_Type.map_func ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let C05Map_Map_Type.C_Map a b =  * self in C05Map_Map_Type.C_Map a ( ^ _12)) ; };
     assume { Inv2.inv ( ^ _12) };
     _11 <- ([#"../05_map.rs" 65 21 65 35] CallMut0.call_mut _12 (v));
diff --git a/creusot/tests/should_succeed/iterators/06_map_precond.mlcfg b/creusot/tests/should_succeed/iterators/06_map_precond.mlcfg
index 9a07dec312..eb3d977edb 100644
--- a/creusot/tests/should_succeed/iterators/06_map_precond.mlcfg
+++ b/creusot/tests/should_succeed/iterators/06_map_precond.mlcfg
@@ -256,7 +256,7 @@ module C06MapPrecond_Impl0_Completed
   predicate completed [#"../06_map_precond.rs" 21 4 21 35] (self : borrowed (C06MapPrecond_Map_Type.t_map i b f Item0.item))
     
    =
-    [#"../06_map_precond.rs" 22 8 25 9] Ghost.inner (C06MapPrecond_Map_Type.map_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = C06MapPrecond_Map_Type.map_iter ( * self); final = C06MapPrecond_Map_Type.map_iter ( ^ self); addr = Borrow.make_new_addr ()} /\ C06MapPrecond_Map_Type.map_func ( * self) = C06MapPrecond_Map_Type.map_func ( ^ self)
+    [#"../06_map_precond.rs" 22 8 25 9] Ghost.inner (C06MapPrecond_Map_Type.map_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = C06MapPrecond_Map_Type.map_iter ( * self); final = C06MapPrecond_Map_Type.map_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1} /\ C06MapPrecond_Map_Type.map_func ( * self) = C06MapPrecond_Map_Type.map_func ( ^ self)
   val completed [#"../06_map_precond.rs" 21 4 21 35] (self : borrowed (C06MapPrecond_Map_Type.t_map i b f Item0.item)) : bool
     ensures { result = completed self }
     
@@ -416,7 +416,7 @@ module C06MapPrecond_Impl1_NextPrecondition_Stub
   use seq.Seq
   clone C06MapPrecond_Common_Iterator_Item_Type as Item0 with
     type self = i
-  predicate next_precondition [#"../06_map_precond.rs" 84 4 84 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  predicate next_precondition [#"../06_map_precond.rs" 83 4 83 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
 end
 module C06MapPrecond_Impl1_NextPrecondition_Interface
   type i
@@ -425,8 +425,8 @@ module C06MapPrecond_Impl1_NextPrecondition_Interface
   use seq.Seq
   clone C06MapPrecond_Common_Iterator_Item_Type as Item0 with
     type self = i
-  predicate next_precondition [#"../06_map_precond.rs" 84 4 84 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
-  val next_precondition [#"../06_map_precond.rs" 84 4 84 74] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
+  predicate next_precondition [#"../06_map_precond.rs" 83 4 83 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  val next_precondition [#"../06_map_precond.rs" 83 4 83 74] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
     ensures { result = next_precondition iter func produced }
     
 end
@@ -450,10 +450,10 @@ module C06MapPrecond_Impl1_NextPrecondition
     type t = Item0.item
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  predicate next_precondition [#"../06_map_precond.rs" 84 4 84 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  predicate next_precondition [#"../06_map_precond.rs" 83 4 83 74] (iter : i) (func : f) (produced : Seq.seq Item0.item)
    =
-    [#"../06_map_precond.rs" 85 8 89 9] forall i : i . forall e : Item0.item . Inv0.inv i -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i -> Precondition0.precondition func (e, Ghost.new produced)
-  val next_precondition [#"../06_map_precond.rs" 84 4 84 74] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
+    [#"../06_map_precond.rs" 84 8 88 9] forall i : i . forall e : Item0.item . Inv0.inv i -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i -> Precondition0.precondition func (e, Ghost.new produced)
+  val next_precondition [#"../06_map_precond.rs" 83 4 83 74] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
     ensures { result = next_precondition iter func produced }
     
 end
@@ -461,14 +461,14 @@ module C06MapPrecond_Impl1_Preservation_Stub
   type i
   type b
   type f
-  predicate preservation [#"../06_map_precond.rs" 106 4 106 45] (iter : i) (func : f)
+  predicate preservation [#"../06_map_precond.rs" 105 4 105 45] (iter : i) (func : f)
 end
 module C06MapPrecond_Impl1_Preservation_Interface
   type i
   type b
   type f
-  predicate preservation [#"../06_map_precond.rs" 106 4 106 45] (iter : i) (func : f)
-  val preservation [#"../06_map_precond.rs" 106 4 106 45] (iter : i) (func : f) : bool
+  predicate preservation [#"../06_map_precond.rs" 105 4 105 45] (iter : i) (func : f)
+  val preservation [#"../06_map_precond.rs" 105 4 105 45] (iter : i) (func : f) : bool
     ensures { result = preservation iter func }
     
 end
@@ -506,9 +506,9 @@ module C06MapPrecond_Impl1_Preservation
     type t = b
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  predicate preservation [#"../06_map_precond.rs" 106 4 106 45] (iter : i) (func : f) =
-    [#"../06_map_precond.rs" 107 8 114 9] forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv1.inv b -> Inv2.inv f -> Inv3.inv e2 -> Inv3.inv e1 -> Inv4.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new s) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new s) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc s e1))
-  val preservation [#"../06_map_precond.rs" 106 4 106 45] (iter : i) (func : f) : bool
+  predicate preservation [#"../06_map_precond.rs" 105 4 105 45] (iter : i) (func : f) =
+    [#"../06_map_precond.rs" 106 8 113 9] forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv1.inv b -> Inv2.inv f -> Inv3.inv e2 -> Inv3.inv e1 -> Inv4.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new s) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new s) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc s e1))
+  val preservation [#"../06_map_precond.rs" 105 4 105 45] (iter : i) (func : f) : bool
     ensures { result = preservation iter func }
     
 end
@@ -516,14 +516,14 @@ module C06MapPrecond_Impl1_Reinitialize_Stub
   type i
   type b
   type f
-  predicate reinitialize [#"../06_map_precond.rs" 118 4 118 29] (_1 : ())
+  predicate reinitialize [#"../06_map_precond.rs" 117 4 117 29] (_1 : ())
 end
 module C06MapPrecond_Impl1_Reinitialize_Interface
   type i
   type b
   type f
-  predicate reinitialize [#"../06_map_precond.rs" 118 4 118 29] (_1 : ())
-  val reinitialize [#"../06_map_precond.rs" 118 4 118 29] (_1 : ()) : bool
+  predicate reinitialize [#"../06_map_precond.rs" 117 4 117 29] (_1 : ())
+  val reinitialize [#"../06_map_precond.rs" 117 4 117 29] (_1 : ()) : bool
     ensures { result = reinitialize _1 }
     
 end
@@ -550,9 +550,9 @@ module C06MapPrecond_Impl1_Reinitialize
     type t = borrowed i
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = f
-  predicate reinitialize [#"../06_map_precond.rs" 118 4 118 29] (_1 : ()) =
-    [#"../06_map_precond.rs" 119 8 124 9] forall func : f . forall iter : borrowed i . Inv0.inv func -> Inv1.inv iter -> Completed0.completed iter -> NextPrecondition0.next_precondition ( ^ iter) func (Seq.empty ) /\ Preservation0.preservation ( ^ iter) func
-  val reinitialize [#"../06_map_precond.rs" 118 4 118 29] (_1 : ()) : bool
+  predicate reinitialize [#"../06_map_precond.rs" 117 4 117 29] (_1 : ()) =
+    [#"../06_map_precond.rs" 118 8 123 9] forall func : f . forall iter : borrowed i . Inv0.inv func -> Inv1.inv iter -> Completed0.completed iter -> NextPrecondition0.next_precondition ( ^ iter) func (Seq.empty ) /\ Preservation0.preservation ( ^ iter) func
+  val reinitialize [#"../06_map_precond.rs" 117 4 117 29] (_1 : ()) : bool
     ensures { result = reinitialize _1 }
     
 end
@@ -898,7 +898,7 @@ module C06MapPrecond_Impl1_PreservationInv_Stub
     type t = f
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  predicate preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  predicate preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
 end
 module C06MapPrecond_Impl1_PreservationInv_Interface
   type i
@@ -918,15 +918,15 @@ module C06MapPrecond_Impl1_PreservationInv_Interface
     type t = f
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  predicate preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
-  val preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
-    requires {[#"../06_map_precond.rs" 94 24 94 28] Inv0.inv iter}
-    requires {[#"../06_map_precond.rs" 94 33 94 37] Inv1.inv func}
-    requires {[#"../06_map_precond.rs" 94 42 94 50] Inv2.inv produced}
-    ensures { [#"../06_map_precond.rs" 93 4 93 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
+  predicate preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  val preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
+    requires {[#"../06_map_precond.rs" 93 24 93 28] Inv0.inv iter}
+    requires {[#"../06_map_precond.rs" 93 33 93 37] Inv1.inv func}
+    requires {[#"../06_map_precond.rs" 93 42 93 50] Inv2.inv produced}
+    ensures { [#"../06_map_precond.rs" 92 4 92 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
     ensures { result = preservation_inv iter func produced }
     
-  axiom preservation_inv_spec : forall iter : i, func : f, produced : Seq.seq Item0.item . ([#"../06_map_precond.rs" 94 24 94 28] Inv0.inv iter) -> ([#"../06_map_precond.rs" 94 33 94 37] Inv1.inv func) -> ([#"../06_map_precond.rs" 94 42 94 50] Inv2.inv produced) -> ([#"../06_map_precond.rs" 93 4 93 83] produced = Seq.empty  -> preservation_inv iter func produced = Preservation0.preservation iter func)
+  axiom preservation_inv_spec : forall iter : i, func : f, produced : Seq.seq Item0.item . ([#"../06_map_precond.rs" 93 24 93 28] Inv0.inv iter) -> ([#"../06_map_precond.rs" 93 33 93 37] Inv1.inv func) -> ([#"../06_map_precond.rs" 93 42 93 50] Inv2.inv produced) -> ([#"../06_map_precond.rs" 92 4 92 83] produced = Seq.empty  -> preservation_inv iter func produced = Preservation0.preservation iter func)
 end
 module C06MapPrecond_Impl1_PreservationInv
   type i
@@ -968,17 +968,17 @@ module C06MapPrecond_Impl1_PreservationInv
     type t = f
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  predicate preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+  predicate preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
    =
-    [#"../06_map_precond.rs" 95 8 102 9] forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv3.inv b -> Inv4.inv f -> Inv5.inv e2 -> Inv5.inv e1 -> Inv2.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new (Seq.(++) produced s)) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new (Seq.(++) produced s)) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc (Seq.(++) produced s) e1))
-  val preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
-    requires {[#"../06_map_precond.rs" 94 24 94 28] Inv0.inv iter}
-    requires {[#"../06_map_precond.rs" 94 33 94 37] Inv1.inv func}
-    requires {[#"../06_map_precond.rs" 94 42 94 50] Inv2.inv produced}
-    ensures { [#"../06_map_precond.rs" 93 4 93 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
+    [#"../06_map_precond.rs" 94 8 101 9] forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv3.inv b -> Inv4.inv f -> Inv5.inv e2 -> Inv5.inv e1 -> Inv2.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new (Seq.(++) produced s)) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new (Seq.(++) produced s)) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc (Seq.(++) produced s) e1))
+  val preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item) : bool
+    requires {[#"../06_map_precond.rs" 93 24 93 28] Inv0.inv iter}
+    requires {[#"../06_map_precond.rs" 93 33 93 37] Inv1.inv func}
+    requires {[#"../06_map_precond.rs" 93 42 93 50] Inv2.inv produced}
+    ensures { [#"../06_map_precond.rs" 92 4 92 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
     ensures { result = preservation_inv iter func produced }
     
-  axiom preservation_inv_spec : forall iter : i, func : f, produced : Seq.seq Item0.item . ([#"../06_map_precond.rs" 94 24 94 28] Inv0.inv iter) -> ([#"../06_map_precond.rs" 94 33 94 37] Inv1.inv func) -> ([#"../06_map_precond.rs" 94 42 94 50] Inv2.inv produced) -> ([#"../06_map_precond.rs" 93 4 93 83] produced = Seq.empty  -> preservation_inv iter func produced = Preservation0.preservation iter func)
+  axiom preservation_inv_spec : forall iter : i, func : f, produced : Seq.seq Item0.item . ([#"../06_map_precond.rs" 93 24 93 28] Inv0.inv iter) -> ([#"../06_map_precond.rs" 93 33 93 37] Inv1.inv func) -> ([#"../06_map_precond.rs" 93 42 93 50] Inv2.inv produced) -> ([#"../06_map_precond.rs" 92 4 92 83] produced = Seq.empty  -> preservation_inv iter func produced = Preservation0.preservation iter func)
 end
 module C06MapPrecond_Impl1_PreservationInv_Impl
   type i
@@ -1113,14 +1113,14 @@ module C06MapPrecond_Impl1_PreservationInv_Impl
     predicate Produces0.produces = Produces0.produces,
     predicate Precondition0.precondition = Precondition0.precondition,
     predicate PostconditionMut0.postcondition_mut = PostconditionMut0.postcondition_mut
-  let rec ghost predicate preservation_inv [#"../06_map_precond.rs" 94 4 94 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
-    requires {[#"../06_map_precond.rs" 94 24 94 28] Inv0.inv iter}
-    requires {[#"../06_map_precond.rs" 94 33 94 37] Inv1.inv func}
-    requires {[#"../06_map_precond.rs" 94 42 94 50] Inv2.inv produced}
-    ensures { [#"../06_map_precond.rs" 93 4 93 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
+  let rec ghost predicate preservation_inv [#"../06_map_precond.rs" 93 4 93 73] (iter : i) (func : f) (produced : Seq.seq Item0.item)
+    requires {[#"../06_map_precond.rs" 93 24 93 28] Inv0.inv iter}
+    requires {[#"../06_map_precond.rs" 93 33 93 37] Inv1.inv func}
+    requires {[#"../06_map_precond.rs" 93 42 93 50] Inv2.inv produced}
+    ensures { [#"../06_map_precond.rs" 92 4 92 83] produced = Seq.empty  -> result = Preservation0.preservation iter func }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
-    [#"../06_map_precond.rs" 95 8 102 9] pure {forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv3.inv b -> Inv4.inv f -> Inv5.inv e2 -> Inv5.inv e1 -> Inv2.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new (Seq.(++) produced s)) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new (Seq.(++) produced s)) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc (Seq.(++) produced s) e1))}
+    [#"../06_map_precond.rs" 94 8 101 9] pure {forall i : i . forall b : b . forall f : borrowed f . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv0.inv i -> Inv3.inv b -> Inv4.inv f -> Inv5.inv e2 -> Inv5.inv e1 -> Inv2.inv s -> Unnest0.unnest func ( * f) -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Precondition0.precondition ( * f) (e1, Ghost.new (Seq.(++) produced s)) -> PostconditionMut0.postcondition_mut f (e1, Ghost.new (Seq.(++) produced s)) b -> Precondition0.precondition ( ^ f) (e2, Ghost.new (Seq.snoc (Seq.(++) produced s) e1))}
 end
 module C06MapPrecond_Impl2_Invariant_Stub
   type i
@@ -1129,7 +1129,7 @@ module C06MapPrecond_Impl2_Invariant_Stub
   clone C06MapPrecond_Common_Iterator_Item_Type as Item0 with
     type self = i
   use C06MapPrecond_Map_Type as C06MapPrecond_Map_Type
-  predicate invariant' [#"../06_map_precond.rs" 158 4 158 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+  predicate invariant' [#"../06_map_precond.rs" 157 4 157 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item)
 end
 module C06MapPrecond_Impl2_Invariant_Interface
   type i
@@ -1138,8 +1138,8 @@ module C06MapPrecond_Impl2_Invariant_Interface
   clone C06MapPrecond_Common_Iterator_Item_Type as Item0 with
     type self = i
   use C06MapPrecond_Map_Type as C06MapPrecond_Map_Type
-  predicate invariant' [#"../06_map_precond.rs" 158 4 158 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item)
-  val invariant' [#"../06_map_precond.rs" 158 4 158 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
+  predicate invariant' [#"../06_map_precond.rs" 157 4 157 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+  val invariant' [#"../06_map_precond.rs" 157 4 157 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
     ensures { result = invariant' self }
     
 end
@@ -1182,9 +1182,9 @@ module C06MapPrecond_Impl2_Invariant
     type b = b,
     type f = f
   use C06MapPrecond_Map_Type as C06MapPrecond_Map_Type
-  predicate invariant' [#"../06_map_precond.rs" 158 4 158 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) =
-    [#"../06_map_precond.rs" 160 12 162 73] Reinitialize0.reinitialize () /\ PreservationInv0.preservation_inv (C06MapPrecond_Map_Type.map_iter self) (C06MapPrecond_Map_Type.map_func self) (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) /\ NextPrecondition0.next_precondition (C06MapPrecond_Map_Type.map_iter self) (C06MapPrecond_Map_Type.map_func self) (Ghost.inner (C06MapPrecond_Map_Type.map_produced self))
-  val invariant' [#"../06_map_precond.rs" 158 4 158 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
+  predicate invariant' [#"../06_map_precond.rs" 157 4 157 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) =
+    [#"../06_map_precond.rs" 159 12 161 73] Reinitialize0.reinitialize () /\ PreservationInv0.preservation_inv (C06MapPrecond_Map_Type.map_iter self) (C06MapPrecond_Map_Type.map_func self) (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) /\ NextPrecondition0.next_precondition (C06MapPrecond_Map_Type.map_iter self) (C06MapPrecond_Map_Type.map_func self) (Ghost.inner (C06MapPrecond_Map_Type.map_produced self))
+  val invariant' [#"../06_map_precond.rs" 157 4 157 30] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
     ensures { result = invariant' self }
     
 end
@@ -1856,7 +1856,7 @@ module C06MapPrecond_Impl1_ProducesOne_Stub
     type t = b
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C06MapPrecond_Map_Type.t_map i b f Item0.item
-  predicate produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+  predicate produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
     
 end
 module C06MapPrecond_Impl1_ProducesOne_Interface
@@ -1876,16 +1876,16 @@ module C06MapPrecond_Impl1_ProducesOne_Interface
     type t = b
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C06MapPrecond_Map_Type.t_map i b f Item0.item
-  predicate produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+  predicate produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
     
-  val produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
-    requires {[#"../06_map_precond.rs" 143 20 143 24] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 143 26 143 33] Inv1.inv visited}
-    requires {[#"../06_map_precond.rs" 143 38 143 42] Inv0.inv succ}
-    ensures { [#"../06_map_precond.rs" 142 14 142 68] result = Produces0.produces self (Seq.singleton visited) succ }
+  val produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
+    requires {[#"../06_map_precond.rs" 142 20 142 24] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 142 26 142 33] Inv1.inv visited}
+    requires {[#"../06_map_precond.rs" 142 38 142 42] Inv0.inv succ}
+    ensures { [#"../06_map_precond.rs" 141 14 141 68] result = Produces0.produces self (Seq.singleton visited) succ }
     ensures { result = produces_one self visited succ }
     
-  axiom produces_one_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, visited : b, succ : C06MapPrecond_Map_Type.t_map i b f Item0.item . ([#"../06_map_precond.rs" 143 20 143 24] Inv0.inv self) -> ([#"../06_map_precond.rs" 143 26 143 33] Inv1.inv visited) -> ([#"../06_map_precond.rs" 143 38 143 42] Inv0.inv succ) -> ([#"../06_map_precond.rs" 142 14 142 68] produces_one self visited succ = Produces0.produces self (Seq.singleton visited) succ)
+  axiom produces_one_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, visited : b, succ : C06MapPrecond_Map_Type.t_map i b f Item0.item . ([#"../06_map_precond.rs" 142 20 142 24] Inv0.inv self) -> ([#"../06_map_precond.rs" 142 26 142 33] Inv1.inv visited) -> ([#"../06_map_precond.rs" 142 38 142 42] Inv0.inv succ) -> ([#"../06_map_precond.rs" 141 14 141 68] produces_one self visited succ = Produces0.produces self (Seq.singleton visited) succ)
 end
 module C06MapPrecond_Impl1_ProducesOne
   type i
@@ -1922,18 +1922,18 @@ module C06MapPrecond_Impl1_ProducesOne
     type t = b
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = C06MapPrecond_Map_Type.t_map i b f Item0.item
-  predicate produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+  predicate produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
     
    =
-    [#"../06_map_precond.rs" 144 8 150 9] exists f : borrowed f . Inv2.inv f /\  * f = C06MapPrecond_Map_Type.map_func self /\  ^ f = C06MapPrecond_Map_Type.map_func succ /\ (exists e : Item0.item . Inv3.inv e /\ Produces1.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) (C06MapPrecond_Map_Type.map_iter succ) /\ Ghost.inner (C06MapPrecond_Map_Type.map_produced succ) = Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e /\ Precondition0.precondition ( * f) (e, C06MapPrecond_Map_Type.map_produced self) /\ PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) visited)
-  val produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
-    requires {[#"../06_map_precond.rs" 143 20 143 24] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 143 26 143 33] Inv1.inv visited}
-    requires {[#"../06_map_precond.rs" 143 38 143 42] Inv0.inv succ}
-    ensures { [#"../06_map_precond.rs" 142 14 142 68] result = Produces0.produces self (Seq.singleton visited) succ }
+    [#"../06_map_precond.rs" 143 8 149 9] exists f : borrowed f . Inv2.inv f /\  * f = C06MapPrecond_Map_Type.map_func self /\  ^ f = C06MapPrecond_Map_Type.map_func succ /\ (exists e : Item0.item . Inv3.inv e /\ Produces1.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) (C06MapPrecond_Map_Type.map_iter succ) /\ Ghost.inner (C06MapPrecond_Map_Type.map_produced succ) = Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e /\ Precondition0.precondition ( * f) (e, C06MapPrecond_Map_Type.map_produced self) /\ PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) visited)
+  val produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item) : bool
+    requires {[#"../06_map_precond.rs" 142 20 142 24] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 142 26 142 33] Inv1.inv visited}
+    requires {[#"../06_map_precond.rs" 142 38 142 42] Inv0.inv succ}
+    ensures { [#"../06_map_precond.rs" 141 14 141 68] result = Produces0.produces self (Seq.singleton visited) succ }
     ensures { result = produces_one self visited succ }
     
-  axiom produces_one_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, visited : b, succ : C06MapPrecond_Map_Type.t_map i b f Item0.item . ([#"../06_map_precond.rs" 143 20 143 24] Inv0.inv self) -> ([#"../06_map_precond.rs" 143 26 143 33] Inv1.inv visited) -> ([#"../06_map_precond.rs" 143 38 143 42] Inv0.inv succ) -> ([#"../06_map_precond.rs" 142 14 142 68] produces_one self visited succ = Produces0.produces self (Seq.singleton visited) succ)
+  axiom produces_one_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, visited : b, succ : C06MapPrecond_Map_Type.t_map i b f Item0.item . ([#"../06_map_precond.rs" 142 20 142 24] Inv0.inv self) -> ([#"../06_map_precond.rs" 142 26 142 33] Inv1.inv visited) -> ([#"../06_map_precond.rs" 142 38 142 42] Inv0.inv succ) -> ([#"../06_map_precond.rs" 141 14 141 68] produces_one self visited succ = Produces0.produces self (Seq.singleton visited) succ)
 end
 module C06MapPrecond_Impl1_ProducesOne_Impl
   type i
@@ -2177,14 +2177,14 @@ module C06MapPrecond_Impl1_ProducesOne_Impl
     predicate Inv1.inv = Inv6.inv,
     predicate Inv2.inv = Inv7.inv,
     axiom .
-  let rec ghost predicate produces_one [#"../06_map_precond.rs" 143 4 143 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
-    requires {[#"../06_map_precond.rs" 143 20 143 24] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 143 26 143 33] Inv1.inv visited}
-    requires {[#"../06_map_precond.rs" 143 38 143 42] Inv0.inv succ}
-    ensures { [#"../06_map_precond.rs" 142 14 142 68] result = Produces0.produces self (Seq.singleton visited) succ }
+  let rec ghost predicate produces_one [#"../06_map_precond.rs" 142 4 142 57] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (visited : b) (succ : C06MapPrecond_Map_Type.t_map i b f Item0.item)
+    requires {[#"../06_map_precond.rs" 142 20 142 24] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 142 26 142 33] Inv1.inv visited}
+    requires {[#"../06_map_precond.rs" 142 38 142 42] Inv0.inv succ}
+    ensures { [#"../06_map_precond.rs" 141 14 141 68] result = Produces0.produces self (Seq.singleton visited) succ }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
-    [#"../06_map_precond.rs" 144 8 150 9] pure {exists f : borrowed f . Inv2.inv f /\  * f = C06MapPrecond_Map_Type.map_func self /\  ^ f = C06MapPrecond_Map_Type.map_func succ /\ (exists e : Item0.item . Inv3.inv e /\ Produces1.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) (C06MapPrecond_Map_Type.map_iter succ) /\ Ghost.inner (C06MapPrecond_Map_Type.map_produced succ) = Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e /\ Precondition0.precondition ( * f) (e, C06MapPrecond_Map_Type.map_produced self) /\ PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) visited)}
+    [#"../06_map_precond.rs" 143 8 149 9] pure {exists f : borrowed f . Inv2.inv f /\  * f = C06MapPrecond_Map_Type.map_func self /\  ^ f = C06MapPrecond_Map_Type.map_func succ /\ (exists e : Item0.item . Inv3.inv e /\ Produces1.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) (C06MapPrecond_Map_Type.map_iter succ) /\ Ghost.inner (C06MapPrecond_Map_Type.map_produced succ) = Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e /\ Precondition0.precondition ( * f) (e, C06MapPrecond_Map_Type.map_produced self) /\ PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) visited)}
 end
 module CreusotContracts_Resolve_Impl1_Resolve_Stub
   type t
@@ -2294,6 +2294,15 @@ module Core_Ops_Function_FnMut_CallMut_Interface
     ensures { Inv2.inv result }
     
 end
+module TyInv_Borrow
+  type t
+  use prelude.Borrow
+  clone CreusotContracts_Invariant_Inv_Stub as Inv1 with
+    type t = t
+  clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
+    type t = borrowed t
+  axiom inv_borrow [@rewrite] : forall self : borrowed t . Inv0.inv self = (Inv1.inv ( * self) /\ Inv1.inv ( ^ self))
+end
 module C06MapPrecond_Impl1_ProducesOneInvariant_Stub
   type i
   type b
@@ -2346,7 +2355,7 @@ module C06MapPrecond_Impl1_ProducesOneInvariant_Stub
   clone C06MapPrecond_Common_Iterator_Produces_Stub as Produces0 with
     type self = i,
     type Item0.item = Item0.item
-  function produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+  function produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
     
 end
 module C06MapPrecond_Impl1_ProducesOneInvariant_Interface
@@ -2401,22 +2410,22 @@ module C06MapPrecond_Impl1_ProducesOneInvariant_Interface
   clone C06MapPrecond_Common_Iterator_Produces_Stub as Produces0 with
     type self = i,
     type Item0.item = Item0.item
-  function produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+  function produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
     
-  val produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 128 4 128 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
-    requires {[#"../06_map_precond.rs" 129 15 129 30]  * f = C06MapPrecond_Map_Type.map_func self}
-    requires {[#"../06_map_precond.rs" 130 15 130 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
-    requires {[#"../06_map_precond.rs" 133 30 133 34] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 133 36 133 37] Inv1.inv e}
-    requires {[#"../06_map_precond.rs" 133 48 133 49] Inv2.inv r}
-    requires {[#"../06_map_precond.rs" 133 54 133 55] Inv3.inv f}
-    requires {[#"../06_map_precond.rs" 133 65 133 69] Inv4.inv iter}
-    ensures { [#"../06_map_precond.rs" 131 14 131 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
-    ensures { [#"../06_map_precond.rs" 132 14 132 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+  val produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 127 4 127 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
+    requires {[#"../06_map_precond.rs" 128 15 128 30]  * f = C06MapPrecond_Map_Type.map_func self}
+    requires {[#"../06_map_precond.rs" 129 15 129 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
+    requires {[#"../06_map_precond.rs" 132 30 132 34] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 132 36 132 37] Inv1.inv e}
+    requires {[#"../06_map_precond.rs" 132 48 132 49] Inv2.inv r}
+    requires {[#"../06_map_precond.rs" 132 54 132 55] Inv3.inv f}
+    requires {[#"../06_map_precond.rs" 132 65 132 69] Inv4.inv iter}
+    ensures { [#"../06_map_precond.rs" 130 14 130 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+    ensures { [#"../06_map_precond.rs" 131 14 131 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
     ensures { result = produces_one_invariant self e r f iter }
     
-  axiom produces_one_invariant_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, e : Item0.item, r : b, f : borrowed f, iter : i . ([#"../06_map_precond.rs" 128 4 128 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter) -> ([#"../06_map_precond.rs" 129 15 129 30]  * f = C06MapPrecond_Map_Type.map_func self) -> ([#"../06_map_precond.rs" 130 15 130 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r) -> ([#"../06_map_precond.rs" 133 30 133 34] Inv0.inv self) -> ([#"../06_map_precond.rs" 133 36 133 37] Inv1.inv e) -> ([#"../06_map_precond.rs" 133 48 133 49] Inv2.inv r) -> ([#"../06_map_precond.rs" 133 54 133 55] Inv3.inv f) -> ([#"../06_map_precond.rs" 133 65 133 69] Inv4.inv iter) -> ([#"../06_map_precond.rs" 132 14 132 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e)) && ([#"../06_map_precond.rs" 131 14 131 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e))
+  axiom produces_one_invariant_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, e : Item0.item, r : b, f : borrowed f, iter : i . ([#"../06_map_precond.rs" 127 4 127 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter) -> ([#"../06_map_precond.rs" 128 15 128 30]  * f = C06MapPrecond_Map_Type.map_func self) -> ([#"../06_map_precond.rs" 129 15 129 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r) -> ([#"../06_map_precond.rs" 132 30 132 34] Inv0.inv self) -> ([#"../06_map_precond.rs" 132 36 132 37] Inv1.inv e) -> ([#"../06_map_precond.rs" 132 48 132 49] Inv2.inv r) -> ([#"../06_map_precond.rs" 132 54 132 55] Inv3.inv f) -> ([#"../06_map_precond.rs" 132 65 132 69] Inv4.inv iter) -> ([#"../06_map_precond.rs" 131 14 131 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e)) && ([#"../06_map_precond.rs" 130 14 130 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e))
 end
 module C06MapPrecond_Impl1_ProducesOneInvariant
   type i
@@ -2470,22 +2479,22 @@ module C06MapPrecond_Impl1_ProducesOneInvariant
   clone C06MapPrecond_Common_Iterator_Produces_Stub as Produces0 with
     type self = i,
     type Item0.item = Item0.item
-  function produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+  function produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
     
-  val produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 128 4 128 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
-    requires {[#"../06_map_precond.rs" 129 15 129 30]  * f = C06MapPrecond_Map_Type.map_func self}
-    requires {[#"../06_map_precond.rs" 130 15 130 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
-    requires {[#"../06_map_precond.rs" 133 30 133 34] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 133 36 133 37] Inv1.inv e}
-    requires {[#"../06_map_precond.rs" 133 48 133 49] Inv2.inv r}
-    requires {[#"../06_map_precond.rs" 133 54 133 55] Inv3.inv f}
-    requires {[#"../06_map_precond.rs" 133 65 133 69] Inv4.inv iter}
-    ensures { [#"../06_map_precond.rs" 131 14 131 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
-    ensures { [#"../06_map_precond.rs" 132 14 132 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+  val produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 127 4 127 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
+    requires {[#"../06_map_precond.rs" 128 15 128 30]  * f = C06MapPrecond_Map_Type.map_func self}
+    requires {[#"../06_map_precond.rs" 129 15 129 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
+    requires {[#"../06_map_precond.rs" 132 30 132 34] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 132 36 132 37] Inv1.inv e}
+    requires {[#"../06_map_precond.rs" 132 48 132 49] Inv2.inv r}
+    requires {[#"../06_map_precond.rs" 132 54 132 55] Inv3.inv f}
+    requires {[#"../06_map_precond.rs" 132 65 132 69] Inv4.inv iter}
+    ensures { [#"../06_map_precond.rs" 130 14 130 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+    ensures { [#"../06_map_precond.rs" 131 14 131 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
     ensures { result = produces_one_invariant self e r f iter }
     
-  axiom produces_one_invariant_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, e : Item0.item, r : b, f : borrowed f, iter : i . ([#"../06_map_precond.rs" 128 4 128 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter) -> ([#"../06_map_precond.rs" 129 15 129 30]  * f = C06MapPrecond_Map_Type.map_func self) -> ([#"../06_map_precond.rs" 130 15 130 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r) -> ([#"../06_map_precond.rs" 133 30 133 34] Inv0.inv self) -> ([#"../06_map_precond.rs" 133 36 133 37] Inv1.inv e) -> ([#"../06_map_precond.rs" 133 48 133 49] Inv2.inv r) -> ([#"../06_map_precond.rs" 133 54 133 55] Inv3.inv f) -> ([#"../06_map_precond.rs" 133 65 133 69] Inv4.inv iter) -> ([#"../06_map_precond.rs" 132 14 132 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e)) && ([#"../06_map_precond.rs" 131 14 131 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e))
+  axiom produces_one_invariant_spec : forall self : C06MapPrecond_Map_Type.t_map i b f Item0.item, e : Item0.item, r : b, f : borrowed f, iter : i . ([#"../06_map_precond.rs" 127 4 127 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter) -> ([#"../06_map_precond.rs" 128 15 128 30]  * f = C06MapPrecond_Map_Type.map_func self) -> ([#"../06_map_precond.rs" 129 15 129 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r) -> ([#"../06_map_precond.rs" 132 30 132 34] Inv0.inv self) -> ([#"../06_map_precond.rs" 132 36 132 37] Inv1.inv e) -> ([#"../06_map_precond.rs" 132 48 132 49] Inv2.inv r) -> ([#"../06_map_precond.rs" 132 54 132 55] Inv3.inv f) -> ([#"../06_map_precond.rs" 132 65 132 69] Inv4.inv iter) -> ([#"../06_map_precond.rs" 131 14 131 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e)) && ([#"../06_map_precond.rs" 130 14 130 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e))
 end
 module C06MapPrecond_Impl1_ProducesOneInvariant_Impl
   type i
@@ -2689,29 +2698,20 @@ module C06MapPrecond_Impl1_ProducesOneInvariant_Impl
     predicate Produces0.produces = Produces0.produces,
     type Item0.item = Item0.item,
     axiom .
-  let rec ghost function produces_one_invariant [#"../06_map_precond.rs" 133 4 133 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 128 4 128 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
-    requires {[#"../06_map_precond.rs" 129 15 129 30]  * f = C06MapPrecond_Map_Type.map_func self}
-    requires {[#"../06_map_precond.rs" 130 15 130 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
-    requires {[#"../06_map_precond.rs" 133 30 133 34] Inv0.inv self}
-    requires {[#"../06_map_precond.rs" 133 36 133 37] Inv1.inv e}
-    requires {[#"../06_map_precond.rs" 133 48 133 49] Inv2.inv r}
-    requires {[#"../06_map_precond.rs" 133 54 133 55] Inv3.inv f}
-    requires {[#"../06_map_precond.rs" 133 65 133 69] Inv4.inv iter}
-    ensures { [#"../06_map_precond.rs" 131 14 131 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
-    ensures { [#"../06_map_precond.rs" 132 14 132 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+  let rec ghost function produces_one_invariant [#"../06_map_precond.rs" 132 4 132 73] (self : C06MapPrecond_Map_Type.t_map i b f Item0.item) (e : Item0.item) (r : b) (f : borrowed f) (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 127 4 127 60] Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.singleton e) iter}
+    requires {[#"../06_map_precond.rs" 128 15 128 30]  * f = C06MapPrecond_Map_Type.map_func self}
+    requires {[#"../06_map_precond.rs" 129 15 129 57] PostconditionMut0.postcondition_mut f (e, C06MapPrecond_Map_Type.map_produced self) r}
+    requires {[#"../06_map_precond.rs" 132 30 132 34] Inv0.inv self}
+    requires {[#"../06_map_precond.rs" 132 36 132 37] Inv1.inv e}
+    requires {[#"../06_map_precond.rs" 132 48 132 49] Inv2.inv r}
+    requires {[#"../06_map_precond.rs" 132 54 132 55] Inv3.inv f}
+    requires {[#"../06_map_precond.rs" 132 65 132 69] Inv4.inv iter}
+    ensures { [#"../06_map_precond.rs" 130 14 130 69] PreservationInv0.preservation_inv iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
+    ensures { [#"../06_map_precond.rs" 131 14 131 70] NextPrecondition0.next_precondition iter ( ^ f) (Seq.snoc (Ghost.inner (C06MapPrecond_Map_Type.map_produced self)) e) }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
-    [#"../06_map_precond.rs" 127 4 127 12] let _ = let a = pure {forall i : i . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv4.inv i -> Inv1.inv e2 -> Inv1.inv e1 -> Inv5.inv s -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.snoc (Seq.snoc (Seq.(++) (Seq.singleton e) s) e1) e2) i} in assert {a} in ()
-end
-module TyInv_Borrow
-  type t
-  use prelude.Borrow
-  clone CreusotContracts_Invariant_Inv_Stub as Inv1 with
-    type t = t
-  clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
-    type t = borrowed t
-  axiom inv_borrow [@rewrite] : forall self : borrowed t . Inv0.inv self = (Inv1.inv ( * self) /\ Inv1.inv ( ^ self))
+    [#"../06_map_precond.rs" 126 4 126 12] let _ = let a = pure {forall i : i . forall e2 : Item0.item . forall e1 : Item0.item . forall s : Seq.seq Item0.item . Inv4.inv i -> Inv1.inv e2 -> Inv1.inv e1 -> Inv5.inv s -> Produces0.produces iter (Seq.snoc (Seq.snoc s e1) e2) i -> Produces0.produces (C06MapPrecond_Map_Type.map_iter self) (Seq.snoc (Seq.snoc (Seq.(++) (Seq.singleton e) s) e1) e2) i} in assert {a} in ()
 end
 module C06MapPrecond_Impl0_Next_Interface
   type i
@@ -3023,9 +3023,7 @@ module C06MapPrecond_Impl0_Next
     type f = f,
     type Item0.item = Item0.item,
     predicate Completed0.completed = Completed1.completed
-  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve3 with
-    type t = C06MapPrecond_Map_Type.t_map i b f Item0.item
-  clone CreusotContracts_Resolve_Resolve_Resolve_Interface as Resolve2 with
+  clone CreusotContracts_Resolve_Resolve_Resolve_Interface as Resolve3 with
     type self = Ghost.ghost_ty ()
   clone C06MapPrecond_Impl1_ProducesOneInvariant as ProducesOneInvariant0 with
     type i = i,
@@ -3045,6 +3043,8 @@ module C06MapPrecond_Impl0_Next
     predicate Inv6.inv = Inv2.inv,
     predicate Preservation0.preservation = Preservation0.preservation,
     axiom .
+  clone CreusotContracts_Resolve_Impl1_Resolve as Resolve2 with
+    type t = C06MapPrecond_Map_Type.t_map i b f Item0.item
   clone CreusotContracts_Resolve_Resolve_Resolve_Interface as Resolve1 with
     type self = Ghost.ghost_ty (Seq.seq Item0.item)
   clone Core_Ops_Function_FnMut_CallMut_Interface as CallMut0 with
@@ -3088,7 +3088,7 @@ module C06MapPrecond_Impl0_Next
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut (C06MapPrecond_Map_Type.map_iter ( * self));
+    _4 <- Borrow.borrow_final (C06MapPrecond_Map_Type.map_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C06MapPrecond_Map_Type.C_Map a b c =  * self in C06MapPrecond_Map_Type.C_Map ( ^ _4) b c) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../06_map_precond.rs" 64 14 64 30] Next0.next _4);
@@ -3104,7 +3104,7 @@ module C06MapPrecond_Impl0_Next
   BB2 {
     assert { [@expl:type invariant] Inv1.inv _3 };
     assume { Resolve0.resolve _3 };
-    _20 <- ([#"../06_map_precond.rs" 75 32 75 50] Ghost.new (Seq.empty ));
+    _20 <- ([#"../06_map_precond.rs" 74 32 74 50] Ghost.new (Seq.empty ));
     goto BB14
   }
   BB3 {
@@ -3114,7 +3114,7 @@ module C06MapPrecond_Impl0_Next
     assert { [@expl:type invariant] Inv1.inv _3 };
     assume { Resolve0.resolve _3 };
     assert { [@expl:type invariant] Inv4.inv self };
-    assume { Resolve3.resolve self };
+    assume { Resolve2.resolve self };
     absurd
   }
   BB5 {
@@ -3130,7 +3130,7 @@ module C06MapPrecond_Impl0_Next
     goto BB7
   }
   BB7 {
-    _12 <- Borrow.borrow_mut (C06MapPrecond_Map_Type.map_func ( * self));
+    _12 <- Borrow.borrow_final (C06MapPrecond_Map_Type.map_func ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let C06MapPrecond_Map_Type.C_Map a b c =  * self in C06MapPrecond_Map_Type.C_Map a ( ^ _12) c) ; };
     assume { Inv2.inv ( ^ _12) };
     r <- ([#"../06_map_precond.rs" 68 24 68 53] CallMut0.call_mut _12 (v, C06MapPrecond_Map_Type.map_produced ( * self)));
@@ -3145,13 +3145,15 @@ module C06MapPrecond_Impl0_Next
     assert { [@expl:type invariant] Inv3.inv produced };
     assume { Resolve1.resolve produced };
     self <- { self with current = (let C06MapPrecond_Map_Type.C_Map a b c =  * self in C06MapPrecond_Map_Type.C_Map a b produced) ; };
+    assert { [@expl:type invariant] Inv3.inv (C06MapPrecond_Map_Type.map_produced ( * self)) };
+    assume { Resolve1.resolve (C06MapPrecond_Map_Type.map_produced ( * self)) };
+    assert { [@expl:type invariant] Inv4.inv self };
+    assume { Resolve2.resolve self };
     _17 <- ([#"../06_map_precond.rs" 70 16 70 52] Ghost.new ());
     goto BB10
   }
   BB10 {
-    assume { Resolve2.resolve _17 };
-    assert { [@expl:type invariant] Inv4.inv self };
-    assume { Resolve3.resolve self };
+    assume { Resolve3.resolve _17 };
     _0 <- Core_Option_Option_Type.C_Some r;
     r <- any b;
     goto BB11
@@ -3171,7 +3173,7 @@ module C06MapPrecond_Impl0_Next
     assert { [@expl:type invariant] Inv3.inv (C06MapPrecond_Map_Type.map_produced ( * self)) };
     assume { Resolve1.resolve (C06MapPrecond_Map_Type.map_produced ( * self)) };
     assert { [@expl:type invariant] Inv4.inv self };
-    assume { Resolve3.resolve self };
+    assume { Resolve2.resolve self };
     _0 <- Core_Option_Option_Type.C_None;
     goto BB15
   }
@@ -3216,14 +3218,14 @@ module C06MapPrecond_Map_Interface
     type t = Item0.item
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  val map [#"../06_map_precond.rs" 171 0 174 17] (iter : i) (func : f) : C06MapPrecond_Map_Type.t_map i b f Item0.item
-    requires {[#"../06_map_precond.rs" 167 0 167 128] forall i2 : i . forall e : Item0.item . Inv0.inv i2 -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i2 -> Precondition0.precondition func (e, Ghost.new (Seq.empty ))}
-    requires {[#"../06_map_precond.rs" 168 11 168 41] Reinitialize0.reinitialize ()}
-    requires {[#"../06_map_precond.rs" 169 11 169 51] Preservation0.preservation iter func}
-    requires {[#"../06_map_precond.rs" 172 4 172 8] Inv0.inv iter}
-    requires {[#"../06_map_precond.rs" 173 4 173 8] Inv2.inv func}
-    ensures { [#"../06_map_precond.rs" 170 10 170 72] result = C06MapPrecond_Map_Type.C_Map iter func (Ghost.new (Seq.empty )) }
-    ensures { [#"../06_map_precond.rs" 174 5 174 17] Inv3.inv result }
+  val map [#"../06_map_precond.rs" 170 0 173 17] (iter : i) (func : f) : C06MapPrecond_Map_Type.t_map i b f Item0.item
+    requires {[#"../06_map_precond.rs" 166 0 166 128] forall i2 : i . forall e : Item0.item . Inv0.inv i2 -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i2 -> Precondition0.precondition func (e, Ghost.new (Seq.empty ))}
+    requires {[#"../06_map_precond.rs" 167 11 167 41] Reinitialize0.reinitialize ()}
+    requires {[#"../06_map_precond.rs" 168 11 168 51] Preservation0.preservation iter func}
+    requires {[#"../06_map_precond.rs" 171 4 171 8] Inv0.inv iter}
+    requires {[#"../06_map_precond.rs" 172 4 172 8] Inv2.inv func}
+    ensures { [#"../06_map_precond.rs" 169 10 169 72] result = C06MapPrecond_Map_Type.C_Map iter func (Ghost.new (Seq.empty )) }
+    ensures { [#"../06_map_precond.rs" 173 5 173 17] Inv3.inv result }
     
 end
 module C06MapPrecond_Map
@@ -3428,14 +3430,14 @@ module C06MapPrecond_Map
     predicate Produces0.produces = Produces0.produces,
     type Item0.item = Item0.item,
     axiom .
-  let rec cfg map [#"../06_map_precond.rs" 171 0 174 17] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) (func : f) : C06MapPrecond_Map_Type.t_map i b f Item0.item
-    requires {[#"../06_map_precond.rs" 167 0 167 128] forall i2 : i . forall e : Item0.item . Inv0.inv i2 -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i2 -> Precondition0.precondition func (e, Ghost.new (Seq.empty ))}
-    requires {[#"../06_map_precond.rs" 168 11 168 41] Reinitialize0.reinitialize ()}
-    requires {[#"../06_map_precond.rs" 169 11 169 51] Preservation0.preservation iter func}
-    requires {[#"../06_map_precond.rs" 172 4 172 8] Inv0.inv iter}
-    requires {[#"../06_map_precond.rs" 173 4 173 8] Inv2.inv func}
-    ensures { [#"../06_map_precond.rs" 170 10 170 72] result = C06MapPrecond_Map_Type.C_Map iter func (Ghost.new (Seq.empty )) }
-    ensures { [#"../06_map_precond.rs" 174 5 174 17] Inv3.inv result }
+  let rec cfg map [#"../06_map_precond.rs" 170 0 173 17] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) (func : f) : C06MapPrecond_Map_Type.t_map i b f Item0.item
+    requires {[#"../06_map_precond.rs" 166 0 166 128] forall i2 : i . forall e : Item0.item . Inv0.inv i2 -> Inv1.inv e -> Produces0.produces iter (Seq.singleton e) i2 -> Precondition0.precondition func (e, Ghost.new (Seq.empty ))}
+    requires {[#"../06_map_precond.rs" 167 11 167 41] Reinitialize0.reinitialize ()}
+    requires {[#"../06_map_precond.rs" 168 11 168 51] Preservation0.preservation iter func}
+    requires {[#"../06_map_precond.rs" 171 4 171 8] Inv0.inv iter}
+    requires {[#"../06_map_precond.rs" 172 4 172 8] Inv2.inv func}
+    ensures { [#"../06_map_precond.rs" 169 10 169 72] result = C06MapPrecond_Map_Type.C_Map iter func (Ghost.new (Seq.empty )) }
+    ensures { [#"../06_map_precond.rs" 173 5 173 17] Inv3.inv result }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : C06MapPrecond_Map_Type.t_map i b f Item0.item;
@@ -3455,7 +3457,7 @@ module C06MapPrecond_Map
     goto BB3
   }
   BB3 {
-    _9 <- ([#"../06_map_precond.rs" 175 32 175 48] Ghost.new (Seq.empty ));
+    _9 <- ([#"../06_map_precond.rs" 174 32 174 48] Ghost.new (Seq.empty ));
     goto BB4
   }
   BB4 {
@@ -3498,28 +3500,28 @@ module C06MapPrecond_Identity_Closure0_Interface
     type t = Ghost.ghost_ty (Seq.seq Item0.item)
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = Item0.item
-  predicate resolve [#"../06_map_precond.rs" 179 14 179 20] (_1 : c06mapprecond_identity_closure0 i) =
+  predicate resolve [#"../06_map_precond.rs" 178 14 178 20] (_1 : c06mapprecond_identity_closure0 i) =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate unnest [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (_2 : c06mapprecond_identity_closure0 i)
+  predicate unnest [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (_2 : c06mapprecond_identity_closure0 i)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate precondition [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item)))
+  predicate precondition [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item)))
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] let (x, _3) = args in true
-  predicate postcondition_once [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
+  predicate postcondition_once [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] let (x, _3) = args in true
-  predicate postcondition_mut [#"../06_map_precond.rs" 179 14 179 20] (self : borrowed (c06mapprecond_identity_closure0 i)) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
+  predicate postcondition_mut [#"../06_map_precond.rs" 178 14 178 20] (self : borrowed (c06mapprecond_identity_closure0 i)) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _3) = args in true) /\ unnest ( * self) ( ^ self)
-  val c06MapPrecond_Identity_Closure0 [#"../06_map_precond.rs" 179 14 179 20] (_1 : borrowed (c06mapprecond_identity_closure0 i)) (x : Item0.item) (_3 : Ghost.ghost_ty (Seq.seq Item0.item)) : Item0.item
-    requires {[#"../06_map_precond.rs" 179 15 179 16] Inv0.inv x}
+  val c06MapPrecond_Identity_Closure0 [#"../06_map_precond.rs" 178 14 178 20] (_1 : borrowed (c06mapprecond_identity_closure0 i)) (x : Item0.item) (_3 : Ghost.ghost_ty (Seq.seq Item0.item)) : Item0.item
+    requires {[#"../06_map_precond.rs" 178 15 178 16] Inv0.inv x}
     requires {[#"../06_map_precond.rs" 1 0 1 0] Inv1.inv _3}
-    ensures { [#"../06_map_precond.rs" 179 14 179 20] Inv0.inv result }
+    ensures { [#"../06_map_precond.rs" 178 14 178 20] Inv0.inv result }
     ensures { unnest ( * _1) ( ^ _1) }
     
 end
@@ -3577,28 +3579,28 @@ module C06MapPrecond_Identity_Closure0
     type t = c06mapprecond_identity_closure0 i
   clone CreusotContracts_Resolve_Resolve_Resolve_Interface as Resolve0 with
     type self = Ghost.ghost_ty (Seq.seq Item0.item)
-  predicate resolve [#"../06_map_precond.rs" 179 14 179 20] (_1 : c06mapprecond_identity_closure0 i) =
+  predicate resolve [#"../06_map_precond.rs" 178 14 178 20] (_1 : c06mapprecond_identity_closure0 i) =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate unnest [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (_2 : c06mapprecond_identity_closure0 i)
+  predicate unnest [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (_2 : c06mapprecond_identity_closure0 i)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate precondition [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item)))
+  predicate precondition [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item)))
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] let (x, _3) = args in true
-  predicate postcondition_once [#"../06_map_precond.rs" 179 14 179 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
+  predicate postcondition_once [#"../06_map_precond.rs" 178 14 178 20] (self : c06mapprecond_identity_closure0 i) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] let (x, _3) = args in true
-  predicate postcondition_mut [#"../06_map_precond.rs" 179 14 179 20] (self : borrowed (c06mapprecond_identity_closure0 i)) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
+  predicate postcondition_mut [#"../06_map_precond.rs" 178 14 178 20] (self : borrowed (c06mapprecond_identity_closure0 i)) (args : (Item0.item, Ghost.ghost_ty (Seq.seq Item0.item))) (result : Item0.item)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _3) = args in true) /\ unnest ( * self) ( ^ self)
-  let rec cfg c06MapPrecond_Identity_Closure0 [#"../06_map_precond.rs" 179 14 179 20] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_identity_closure0 i)) (x : Item0.item) (_3 : Ghost.ghost_ty (Seq.seq Item0.item)) : Item0.item
-    requires {[#"../06_map_precond.rs" 179 15 179 16] Inv1.inv x}
+  let rec cfg c06MapPrecond_Identity_Closure0 [#"../06_map_precond.rs" 178 14 178 20] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_identity_closure0 i)) (x : Item0.item) (_3 : Ghost.ghost_ty (Seq.seq Item0.item)) : Item0.item
+    requires {[#"../06_map_precond.rs" 178 15 178 16] Inv1.inv x}
     requires {[#"../06_map_precond.rs" 1 0 1 0] Inv0.inv _3}
-    ensures { [#"../06_map_precond.rs" 179 14 179 20] Inv1.inv result }
+    ensures { [#"../06_map_precond.rs" 178 14 178 20] Inv1.inv result }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : Item0.item;
@@ -3625,8 +3627,8 @@ module C06MapPrecond_Identity_Interface
   type i
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = i
-  val identity [#"../06_map_precond.rs" 178 0 178 37] (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 178 29 178 33] Inv0.inv iter}
+  val identity [#"../06_map_precond.rs" 177 0 177 37] (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 177 29 177 33] Inv0.inv iter}
     
 end
 module C06MapPrecond_Identity
@@ -3793,8 +3795,8 @@ module C06MapPrecond_Identity
     predicate Preservation0.preservation = Preservation0.preservation,
     predicate Inv2.inv = Inv4.inv,
     predicate Inv3.inv = Inv0.inv
-  let rec cfg identity [#"../06_map_precond.rs" 178 0 178 37] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 178 29 178 33] Inv1.inv iter}
+  let rec cfg identity [#"../06_map_precond.rs" 177 0 177 37] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 177 29 177 33] Inv1.inv iter}
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : ();
@@ -3804,7 +3806,7 @@ module C06MapPrecond_Identity
     goto BB0
   }
   BB0 {
-    _2 <- ([#"../06_map_precond.rs" 179 4 179 23] Map0.map iter (Closure00.C06MapPrecond_Identity_Closure0));
+    _2 <- ([#"../06_map_precond.rs" 178 4 178 23] Map0.map iter (Closure00.C06MapPrecond_Identity_Closure0));
     iter <- any i;
     goto BB1
   }
@@ -3835,27 +3837,27 @@ module C06MapPrecond_Increment_Closure2_Interface
   use prelude.Borrow
   use prelude.Ghost
   use seq.Seq
-  predicate resolve [#"../06_map_precond.rs" 190 8 190 35] (_1 : c06mapprecond_increment_closure2 u) =
+  predicate resolve [#"../06_map_precond.rs" 189 8 189 35] (_1 : c06mapprecond_increment_closure2 u) =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate unnest [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (_2 : c06mapprecond_increment_closure2 u)
+  predicate unnest [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (_2 : c06mapprecond_increment_closure2 u)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate precondition [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
+  predicate precondition [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
     
    =
-    [#"../06_map_precond.rs" 189 19 189 27] let (x, _3) = args in UInt32.to_int x <= 15
-  predicate postcondition_once [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 188 19 188 27] let (x, _3) = args in UInt32.to_int x <= 15
+  predicate postcondition_once [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
-    [#"../06_map_precond.rs" 190 18 190 33] let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1
-  predicate postcondition_mut [#"../06_map_precond.rs" 190 8 190 35] (self : borrowed (c06mapprecond_increment_closure2 u)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 189 18 189 33] let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1
+  predicate postcondition_mut [#"../06_map_precond.rs" 189 8 189 35] (self : borrowed (c06mapprecond_increment_closure2 u)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1) /\ unnest ( * self) ( ^ self)
-  val c06MapPrecond_Increment_Closure2 [#"../06_map_precond.rs" 190 8 190 35] (_1 : borrowed (c06mapprecond_increment_closure2 u)) (x : uint32) (_3 : Ghost.ghost_ty (Seq.seq uint32)) : uint32
-    requires {[#"../06_map_precond.rs" 189 19 189 27] UInt32.to_int x <= 15}
-    ensures { [#"../06_map_precond.rs" 190 18 190 33] UInt32.to_int result = UInt32.to_int x + 1 }
+  val c06MapPrecond_Increment_Closure2 [#"../06_map_precond.rs" 189 8 189 35] (_1 : borrowed (c06mapprecond_increment_closure2 u)) (x : uint32) (_3 : Ghost.ghost_ty (Seq.seq uint32)) : uint32
+    requires {[#"../06_map_precond.rs" 188 19 188 27] UInt32.to_int x <= 15}
+    ensures { [#"../06_map_precond.rs" 189 18 189 33] UInt32.to_int result = UInt32.to_int x + 1 }
     ensures { unnest ( * _1) ( ^ _1) }
     
 end
@@ -3871,27 +3873,27 @@ module C06MapPrecond_Increment_Closure2
   use prelude.Ghost
   clone CreusotContracts_Resolve_Impl1_Resolve as Resolve0 with
     type t = c06mapprecond_increment_closure2 u
-  predicate resolve [#"../06_map_precond.rs" 190 8 190 35] (_1 : c06mapprecond_increment_closure2 u) =
+  predicate resolve [#"../06_map_precond.rs" 189 8 189 35] (_1 : c06mapprecond_increment_closure2 u) =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate unnest [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (_2 : c06mapprecond_increment_closure2 u)
+  predicate unnest [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (_2 : c06mapprecond_increment_closure2 u)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] true
-  predicate precondition [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
+  predicate precondition [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
     
    =
-    [#"../06_map_precond.rs" 189 19 189 27] let (x, _3) = args in UInt32.to_int x <= 15
-  predicate postcondition_once [#"../06_map_precond.rs" 190 8 190 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 188 19 188 27] let (x, _3) = args in UInt32.to_int x <= 15
+  predicate postcondition_once [#"../06_map_precond.rs" 189 8 189 35] (self : c06mapprecond_increment_closure2 u) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
-    [#"../06_map_precond.rs" 190 18 190 33] let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1
-  predicate postcondition_mut [#"../06_map_precond.rs" 190 8 190 35] (self : borrowed (c06mapprecond_increment_closure2 u)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 189 18 189 33] let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1
+  predicate postcondition_mut [#"../06_map_precond.rs" 189 8 189 35] (self : borrowed (c06mapprecond_increment_closure2 u)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _3) = args in UInt32.to_int result = UInt32.to_int x + 1) /\ unnest ( * self) ( ^ self)
-  let rec cfg c06MapPrecond_Increment_Closure2 [#"../06_map_precond.rs" 190 8 190 35] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_increment_closure2 u)) (x : uint32) (_3 : Ghost.ghost_ty (Seq.seq uint32)) : uint32
-    requires {[#"../06_map_precond.rs" 189 19 189 27] UInt32.to_int x <= 15}
-    ensures { [#"../06_map_precond.rs" 190 18 190 33] UInt32.to_int result = UInt32.to_int x + 1 }
+  let rec cfg c06MapPrecond_Increment_Closure2 [#"../06_map_precond.rs" 189 8 189 35] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_increment_closure2 u)) (x : uint32) (_3 : Ghost.ghost_ty (Seq.seq uint32)) : uint32
+    requires {[#"../06_map_precond.rs" 188 19 188 27] UInt32.to_int x <= 15}
+    ensures { [#"../06_map_precond.rs" 189 18 189 33] UInt32.to_int result = UInt32.to_int x + 1 }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : uint32;
@@ -3904,7 +3906,7 @@ module C06MapPrecond_Increment_Closure2
   }
   BB0 {
     assume { Resolve0.resolve _1 };
-    res1 <- ([#"../06_map_precond.rs" 191 20 191 25] x + ([#"../06_map_precond.rs" 191 24 191 25] (1 : uint32)));
+    res1 <- ([#"../06_map_precond.rs" 190 20 190 25] x + ([#"../06_map_precond.rs" 190 24 190 25] (1 : uint32)));
     res <- res1;
     _0 <- res;
     return _0
@@ -3926,10 +3928,10 @@ module C06MapPrecond_Increment_Interface
     type self = u
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = borrowed u
-  val increment [#"../06_map_precond.rs" 186 0 186 50] (iter : u) : ()
-    requires {[#"../06_map_precond.rs" 182 0 182 162] forall done_ : borrowed u . Inv0.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : u . Inv1.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
-    requires {[#"../06_map_precond.rs" 183 0 185 2] forall fin : u . forall prod : Seq.seq uint32 . Inv1.inv fin -> Produces0.produces iter prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (10 : uint32))}
-    requires {[#"../06_map_precond.rs" 186 42 186 46] Inv1.inv iter}
+  val increment [#"../06_map_precond.rs" 185 0 185 50] (iter : u) : ()
+    requires {[#"../06_map_precond.rs" 181 0 181 162] forall done_ : borrowed u . Inv0.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : u . Inv1.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
+    requires {[#"../06_map_precond.rs" 182 0 184 2] forall fin : u . forall prod : Seq.seq uint32 . Inv1.inv fin -> Produces0.produces iter prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (10 : uint32))}
+    requires {[#"../06_map_precond.rs" 185 42 185 46] Inv1.inv iter}
     
 end
 module C06MapPrecond_Increment
@@ -4120,10 +4122,10 @@ module C06MapPrecond_Increment
     predicate Preservation0.preservation = Preservation0.preservation,
     predicate Inv2.inv = Inv4.inv,
     predicate Inv3.inv = Inv0.inv
-  let rec cfg increment [#"../06_map_precond.rs" 186 0 186 50] [@cfg:stackify] [@cfg:subregion_analysis] (iter : u) : ()
-    requires {[#"../06_map_precond.rs" 182 0 182 162] forall done_ : borrowed u . Inv1.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : u . Inv2.inv next -> Produces1.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
-    requires {[#"../06_map_precond.rs" 183 0 185 2] forall fin : u . forall prod : Seq.seq uint32 . Inv2.inv fin -> Produces1.produces iter prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (10 : uint32))}
-    requires {[#"../06_map_precond.rs" 186 42 186 46] Inv2.inv iter}
+  let rec cfg increment [#"../06_map_precond.rs" 185 0 185 50] [@cfg:stackify] [@cfg:subregion_analysis] (iter : u) : ()
+    requires {[#"../06_map_precond.rs" 181 0 181 162] forall done_ : borrowed u . Inv1.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : u . Inv2.inv next -> Produces1.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
+    requires {[#"../06_map_precond.rs" 182 0 184 2] forall fin : u . forall prod : Seq.seq uint32 . Inv2.inv fin -> Produces1.produces iter prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (10 : uint32))}
+    requires {[#"../06_map_precond.rs" 185 42 185 46] Inv2.inv iter}
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : ();
@@ -4136,14 +4138,14 @@ module C06MapPrecond_Increment
     goto BB1
   }
   BB1 {
-    i <- ([#"../06_map_precond.rs" 187 12 192 5] Map0.map iter (Closure20.C06MapPrecond_Increment_Closure2));
+    i <- ([#"../06_map_precond.rs" 186 12 191 5] Map0.map iter (Closure20.C06MapPrecond_Increment_Closure2));
     iter <- any u;
     goto BB2
   }
   BB2 {
     assert { [@expl:type invariant] Inv0.inv i };
     assume { Resolve0.resolve i };
-    assert { [@expl:assertion] [#"../06_map_precond.rs" 194 4 197 5] forall fin : C06MapPrecond_Map_Type.t_map u uint32 (Closure20.c06mapprecond_increment_closure2 u) uint32 . forall prod : Seq.seq uint32 . Inv0.inv fin -> Produces0.produces i prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (11 : uint32)) };
+    assert { [@expl:assertion] [#"../06_map_precond.rs" 193 4 196 5] forall fin : C06MapPrecond_Map_Type.t_map u uint32 (Closure20.c06mapprecond_increment_closure2 u) uint32 . forall prod : Seq.seq uint32 . Inv0.inv fin -> Produces0.produces i prod fin -> (forall x : int . 0 <= x /\ x < Seq.length prod -> Seq.get prod x <= (11 : uint32)) };
     goto BB3
   }
   BB3 {
@@ -4189,30 +4191,30 @@ module C06MapPrecond_Counter_Closure2_Interface
   clone CreusotContracts_Resolve_Impl1_Resolve_Stub as Resolve0 with
     type t = usize
   clone Core_Num_Impl11_Max_Stub as Max0
-  let function field_0 [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) : borrowed usize
+  let function field_0 [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) : borrowed usize
    = [@vc:do_not_keep_trace] [@vc:sp]
     [#"../06_map_precond.rs" 1 0 1 0] let C06MapPrecond_Counter_Closure2 a = self in a
-  predicate resolve [#"../06_map_precond.rs" 207 8 207 41] (_1 : c06mapprecond_counter_closure2 i) =
+  predicate resolve [#"../06_map_precond.rs" 206 8 206 41] (_1 : c06mapprecond_counter_closure2 i) =
     [#"../06_map_precond.rs" 1 0 1 0] Resolve0.resolve (field_0 _1)
-  predicate unnest [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (_2 : c06mapprecond_counter_closure2 i)
+  predicate unnest [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (_2 : c06mapprecond_counter_closure2 i)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0]  ^ field_0 _2 =  ^ field_0 self
-  predicate precondition [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
+  predicate precondition [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
     
    =
-    [#"../06_map_precond.rs" 206 19 206 61] let (x, _prod) = args in UIntSize.to_int ( * field_0 self) = Seq.length (Ghost.inner _prod) /\  * field_0 self < Max0.mAX'
-  predicate postcondition_once [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 205 19 205 61] let (x, _prod) = args in UIntSize.to_int ( * field_0 self) = Seq.length (Ghost.inner _prod) /\  * field_0 self < Max0.mAX'
+  predicate postcondition_once [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
-    [#"../06_map_precond.rs" 207 18 207 39] let (x, _prod) = args in UIntSize.to_int ( ^ field_0 self) = UIntSize.to_int ( * field_0 self) + 1
-  predicate postcondition_mut [#"../06_map_precond.rs" 207 8 207 41] (self : borrowed (c06mapprecond_counter_closure2 i)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 206 18 206 39] let (x, _prod) = args in UIntSize.to_int ( ^ field_0 self) = UIntSize.to_int ( * field_0 self) + 1
+  predicate postcondition_mut [#"../06_map_precond.rs" 206 8 206 41] (self : borrowed (c06mapprecond_counter_closure2 i)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _prod) = args in UIntSize.to_int ( * field_0 ( ^ self)) = UIntSize.to_int ( * field_0 ( * self)) + 1) /\ unnest ( * self) ( ^ self)
-  val c06MapPrecond_Counter_Closure2 [#"../06_map_precond.rs" 207 8 207 41] (_1 : borrowed (c06mapprecond_counter_closure2 i)) (x : uint32) (_prod : Ghost.ghost_ty (Seq.seq uint32)) : uint32
-    requires {[#"../06_map_precond.rs" 206 19 206 61] UIntSize.to_int ( * field_0 ( * _1)) = Seq.length (Ghost.inner _prod) /\  * field_0 ( * _1) < Max0.mAX'}
-    ensures { [#"../06_map_precond.rs" 207 18 207 39] UIntSize.to_int ( * field_0 ( ^ _1)) = UIntSize.to_int ( * field_0 ( * _1)) + 1 }
+  val c06MapPrecond_Counter_Closure2 [#"../06_map_precond.rs" 206 8 206 41] (_1 : borrowed (c06mapprecond_counter_closure2 i)) (x : uint32) (_prod : Ghost.ghost_ty (Seq.seq uint32)) : uint32
+    requires {[#"../06_map_precond.rs" 205 19 205 61] UIntSize.to_int ( * field_0 ( * _1)) = Seq.length (Ghost.inner _prod) /\  * field_0 ( * _1) < Max0.mAX'}
+    ensures { [#"../06_map_precond.rs" 206 18 206 39] UIntSize.to_int ( * field_0 ( ^ _1)) = UIntSize.to_int ( * field_0 ( * _1)) + 1 }
     ensures { unnest ( * _1) ( ^ _1) }
     
 end
@@ -4232,30 +4234,30 @@ module C06MapPrecond_Counter_Closure2
   clone Core_Num_Impl11_Max as Max0
   clone CreusotContracts_Resolve_Impl1_Resolve as Resolve0 with
     type t = c06mapprecond_counter_closure2 i
-  let function field_0 [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) : borrowed usize
+  let function field_0 [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) : borrowed usize
    = [@vc:do_not_keep_trace] [@vc:sp]
     [#"../06_map_precond.rs" 1 0 1 0] let C06MapPrecond_Counter_Closure2 a = self in a
-  predicate resolve [#"../06_map_precond.rs" 207 8 207 41] (_1 : c06mapprecond_counter_closure2 i) =
+  predicate resolve [#"../06_map_precond.rs" 206 8 206 41] (_1 : c06mapprecond_counter_closure2 i) =
     [#"../06_map_precond.rs" 1 0 1 0] Resolve1.resolve (field_0 _1)
-  predicate unnest [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (_2 : c06mapprecond_counter_closure2 i)
+  predicate unnest [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (_2 : c06mapprecond_counter_closure2 i)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0]  ^ field_0 _2 =  ^ field_0 self
-  predicate precondition [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
+  predicate precondition [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32)))
     
    =
-    [#"../06_map_precond.rs" 206 19 206 61] let (x, _prod) = args in UIntSize.to_int ( * field_0 self) = Seq.length (Ghost.inner _prod) /\  * field_0 self < Max0.mAX'
-  predicate postcondition_once [#"../06_map_precond.rs" 207 8 207 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 205 19 205 61] let (x, _prod) = args in UIntSize.to_int ( * field_0 self) = Seq.length (Ghost.inner _prod) /\  * field_0 self < Max0.mAX'
+  predicate postcondition_once [#"../06_map_precond.rs" 206 8 206 41] (self : c06mapprecond_counter_closure2 i) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
-    [#"../06_map_precond.rs" 207 18 207 39] let (x, _prod) = args in UIntSize.to_int ( ^ field_0 self) = UIntSize.to_int ( * field_0 self) + 1
-  predicate postcondition_mut [#"../06_map_precond.rs" 207 8 207 41] (self : borrowed (c06mapprecond_counter_closure2 i)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
+    [#"../06_map_precond.rs" 206 18 206 39] let (x, _prod) = args in UIntSize.to_int ( ^ field_0 self) = UIntSize.to_int ( * field_0 self) + 1
+  predicate postcondition_mut [#"../06_map_precond.rs" 206 8 206 41] (self : borrowed (c06mapprecond_counter_closure2 i)) (args : (uint32, Ghost.ghost_ty (Seq.seq uint32))) (result : uint32)
     
    =
     [#"../06_map_precond.rs" 1 0 1 0] (let (x, _prod) = args in UIntSize.to_int ( * field_0 ( ^ self)) = UIntSize.to_int ( * field_0 ( * self)) + 1) /\ unnest ( * self) ( ^ self)
-  let rec cfg c06MapPrecond_Counter_Closure2 [#"../06_map_precond.rs" 207 8 207 41] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_counter_closure2 i)) (x : uint32) (_prod : Ghost.ghost_ty (Seq.seq uint32)) : uint32
-    requires {[#"../06_map_precond.rs" 206 19 206 61] UIntSize.to_int ( * field_0 ( * _1)) = Seq.length (Ghost.inner _prod) /\  * field_0 ( * _1) < Max0.mAX'}
-    ensures { [#"../06_map_precond.rs" 207 18 207 39] UIntSize.to_int ( * field_0 ( ^ _1)) = UIntSize.to_int ( * field_0 ( * _1)) + 1 }
+  let rec cfg c06MapPrecond_Counter_Closure2 [#"../06_map_precond.rs" 206 8 206 41] [@cfg:stackify] [@cfg:subregion_analysis] (_1 : borrowed (c06mapprecond_counter_closure2 i)) (x : uint32) (_prod : Ghost.ghost_ty (Seq.seq uint32)) : uint32
+    requires {[#"../06_map_precond.rs" 205 19 205 61] UIntSize.to_int ( * field_0 ( * _1)) = Seq.length (Ghost.inner _prod) /\  * field_0 ( * _1) < Max0.mAX'}
+    ensures { [#"../06_map_precond.rs" 206 18 206 39] UIntSize.to_int ( * field_0 ( ^ _1)) = UIntSize.to_int ( * field_0 ( * _1)) + 1 }
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : uint32;
@@ -4267,7 +4269,7 @@ module C06MapPrecond_Counter_Closure2
     goto BB0
   }
   BB0 {
-    _1 <- { _1 with current = (let C06MapPrecond_Counter_Closure2 a =  * _1 in C06MapPrecond_Counter_Closure2 ({ (field_0 ( * _1)) with current = ([#"../06_map_precond.rs" 209 12 209 20]  * field_0 ( * _1) + ([#"../06_map_precond.rs" 209 19 209 20] (1 : usize))) ; })) ; };
+    _1 <- { _1 with current = (let C06MapPrecond_Counter_Closure2 a =  * _1 in C06MapPrecond_Counter_Closure2 ({ (field_0 ( * _1)) with current = ([#"../06_map_precond.rs" 208 12 208 20]  * field_0 ( * _1) + ([#"../06_map_precond.rs" 208 19 208 20] (1 : usize))) ; })) ; };
     assume { Resolve0.resolve _1 };
     res1 <- x;
     res <- res1;
@@ -4293,10 +4295,10 @@ module C06MapPrecond_Counter_Interface
     type self = i
   clone CreusotContracts_Invariant_Inv_Stub as Inv0 with
     type t = borrowed i
-  val counter [#"../06_map_precond.rs" 202 0 202 48] (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 200 0 200 162] forall done_ : borrowed i . Inv0.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : i . Inv1.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
-    requires {[#"../06_map_precond.rs" 201 0 201 92] forall fin : i . forall prod : Seq.seq uint32 . Inv1.inv fin -> Produces0.produces iter prod fin -> Seq.length prod <= UIntSize.to_int Max0.mAX'}
-    requires {[#"../06_map_precond.rs" 202 40 202 44] Inv1.inv iter}
+  val counter [#"../06_map_precond.rs" 201 0 201 48] (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 199 0 199 162] forall done_ : borrowed i . Inv0.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : i . Inv1.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
+    requires {[#"../06_map_precond.rs" 200 0 200 92] forall fin : i . forall prod : Seq.seq uint32 . Inv1.inv fin -> Produces0.produces iter prod fin -> Seq.length prod <= UIntSize.to_int Max0.mAX'}
+    requires {[#"../06_map_precond.rs" 201 40 201 44] Inv1.inv iter}
     
 end
 module C06MapPrecond_Counter
@@ -4459,10 +4461,10 @@ module C06MapPrecond_Counter
     predicate Preservation0.preservation = Preservation0.preservation,
     predicate Inv2.inv = Inv4.inv,
     predicate Inv3.inv = Inv0.inv
-  let rec cfg counter [#"../06_map_precond.rs" 202 0 202 48] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) : ()
-    requires {[#"../06_map_precond.rs" 200 0 200 162] forall done_ : borrowed i . Inv1.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : i . Inv2.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
-    requires {[#"../06_map_precond.rs" 201 0 201 92] forall fin : i . forall prod : Seq.seq uint32 . Inv2.inv fin -> Produces0.produces iter prod fin -> Seq.length prod <= UIntSize.to_int Max0.mAX'}
-    requires {[#"../06_map_precond.rs" 202 40 202 44] Inv2.inv iter}
+  let rec cfg counter [#"../06_map_precond.rs" 201 0 201 48] [@cfg:stackify] [@cfg:subregion_analysis] (iter : i) : ()
+    requires {[#"../06_map_precond.rs" 199 0 199 162] forall done_ : borrowed i . Inv1.inv done_ -> Completed0.completed done_ -> (forall steps : Seq.seq uint32 . forall next : i . Inv2.inv next -> Produces0.produces ( ^ done_) steps next -> steps = Seq.empty  /\  ^ done_ = next)}
+    requires {[#"../06_map_precond.rs" 200 0 200 92] forall fin : i . forall prod : Seq.seq uint32 . Inv2.inv fin -> Produces0.produces iter prod fin -> Seq.length prod <= UIntSize.to_int Max0.mAX'}
+    requires {[#"../06_map_precond.rs" 201 40 201 44] Inv2.inv iter}
     
    = [@vc:do_not_keep_trace] [@vc:sp]
   var _0 : ();
@@ -4477,10 +4479,10 @@ module C06MapPrecond_Counter
     goto BB1
   }
   BB1 {
-    cnt <- ([#"../06_map_precond.rs" 203 18 203 19] (0 : usize));
+    cnt <- ([#"../06_map_precond.rs" 202 18 202 19] (0 : usize));
     _8 <- Borrow.borrow_mut cnt;
     cnt <-  ^ _8;
-    _5 <- ([#"../06_map_precond.rs" 204 4 212 5] Map0.map iter (Closure20.C06MapPrecond_Counter_Closure2 _8));
+    _5 <- ([#"../06_map_precond.rs" 203 4 211 5] Map0.map iter (Closure20.C06MapPrecond_Counter_Closure2 _8));
     iter <- any i;
     _8 <- any borrowed usize;
     goto BB2
diff --git a/creusot/tests/should_succeed/iterators/06_map_precond.rs b/creusot/tests/should_succeed/iterators/06_map_precond.rs
index 6398a3c77d..12fcdfd0c6 100644
--- a/creusot/tests/should_succeed/iterators/06_map_precond.rs
+++ b/creusot/tests/should_succeed/iterators/06_map_precond.rs
@@ -68,7 +68,6 @@ impl<I: Iterator, B, F: FnMut(I::Item, Ghost<Seq<I::Item>>) -> B> Iterator for M
                 let r = (self.func)(v, self.produced);
                 self.produced = produced;
                 gh! { Self::produces_one_invariant };
-                let _ = self; // Make sure self is not resolve until here.
                 Some(r)
             }
             None => {
diff --git a/creusot/tests/should_succeed/iterators/07_fuse.mlcfg b/creusot/tests/should_succeed/iterators/07_fuse.mlcfg
index d77d4ca502..47d5d9bdee 100644
--- a/creusot/tests/should_succeed/iterators/07_fuse.mlcfg
+++ b/creusot/tests/should_succeed/iterators/07_fuse.mlcfg
@@ -497,7 +497,7 @@ module C07Fuse_Impl0_Next
     goto BB0
   }
   BB0 {
-    _3 <- Borrow.borrow_mut (C07Fuse_Fuse_Type.fuse_iter ( * self));
+    _3 <- Borrow.borrow_final (C07Fuse_Fuse_Type.fuse_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C07Fuse_Fuse_Type.C_Fuse a =  * self in C07Fuse_Fuse_Type.C_Fuse ( ^ _3)) ; };
     assume { Inv0.inv ( ^ _3) };
     switch ( * _3)
@@ -509,10 +509,10 @@ module C07Fuse_Impl0_Next
     goto BB4
   }
   BB2 {
-    iter <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _3));
+    iter <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _3)) (Borrow.inherit_id (Borrow.get_id _3) 1);
     _3 <- { _3 with current = (let Core_Option_Option_Type.C_Some a =  * _3 in Core_Option_Option_Type.C_Some ( ^ iter)) ; };
     assume { Inv3.inv ( ^ iter) };
-    _7 <- Borrow.borrow_mut ( * iter);
+    _7 <- Borrow.borrow_final ( * iter) (Borrow.get_id iter);
     iter <- { iter with current = ( ^ _7) ; };
     assume { Inv3.inv ( ^ _7) };
     _6 <- ([#"../07_fuse.rs" 42 32 42 43] Next0.next _7);
diff --git a/creusot/tests/should_succeed/iterators/08_collect_extend.mlcfg b/creusot/tests/should_succeed/iterators/08_collect_extend.mlcfg
index 497c322e9e..d3f4b91f94 100644
--- a/creusot/tests/should_succeed/iterators/08_collect_extend.mlcfg
+++ b/creusot/tests/should_succeed/iterators/08_collect_extend.mlcfg
@@ -891,7 +891,7 @@ module C08CollectExtend_Extend
     _19 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _19;
     assume { Inv3.inv ( ^ _19) };
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     assume { Inv3.inv ( ^ _18) };
     _17 <- ([#"../08_collect_extend.rs" 27 4 27 35] Next0.next _18);
@@ -1344,7 +1344,7 @@ module C08CollectExtend_Collect
     _17 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _17;
     assume { Inv2.inv ( ^ _17) };
-    _16 <- Borrow.borrow_mut ( * _17);
+    _16 <- Borrow.borrow_final ( * _17) (Borrow.get_id _17);
     _17 <- { _17 with current = ( ^ _16) ; };
     assume { Inv2.inv ( ^ _16) };
     _15 <- ([#"../08_collect_extend.rs" 45 4 45 40] Next0.next _16);
@@ -2070,7 +2070,7 @@ module C08CollectExtend_ExtendIndex
   BB2 {
     _9 <- Borrow.borrow_mut v1;
     v1 <-  ^ _9;
-    _8 <- Borrow.borrow_mut ( * _9);
+    _8 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _8) ; };
     _10 <- ([#"../08_collect_extend.rs" 55 20 55 34] IntoIter0.into_iter v2);
     v2 <- any Alloc_Vec_Vec_Type.t_vec uint32 (Alloc_Alloc_Global_Type.t_global);
diff --git a/creusot/tests/should_succeed/iterators/10_once.mlcfg b/creusot/tests/should_succeed/iterators/10_once.mlcfg
index af54485c09..832ebbc7e1 100644
--- a/creusot/tests/should_succeed/iterators/10_once.mlcfg
+++ b/creusot/tests/should_succeed/iterators/10_once.mlcfg
@@ -395,7 +395,7 @@ module C10Once_Impl0_Next
     goto BB0
   }
   BB0 {
-    _3 <- Borrow.borrow_mut (C10Once_Once_Type.once_0 ( * self));
+    _3 <- Borrow.borrow_final (C10Once_Once_Type.once_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C10Once_Once_Type.C_Once a =  * self in C10Once_Once_Type.C_Once ( ^ _3)) ; };
     assume { Inv0.inv ( ^ _3) };
     _0 <- ([#"../10_once.rs" 45 8 45 21] Take0.take _3);
diff --git a/creusot/tests/should_succeed/iterators/12_zip.mlcfg b/creusot/tests/should_succeed/iterators/12_zip.mlcfg
index 75dd3aaa92..19acbf68c6 100644
--- a/creusot/tests/should_succeed/iterators/12_zip.mlcfg
+++ b/creusot/tests/should_succeed/iterators/12_zip.mlcfg
@@ -138,7 +138,7 @@ module C12Zip_Impl0_Completed
     type self = a
   use C12Zip_Zip_Type as C12Zip_Zip_Type
   predicate completed [#"../12_zip.rs" 18 4 18 35] (self : borrowed (C12Zip_Zip_Type.t_zip a b)) =
-    [#"../12_zip.rs" 20 13 22 67] Completed0.completed {current = C12Zip_Zip_Type.zip_a ( * self); final = C12Zip_Zip_Type.zip_a ( ^ self); addr = Borrow.make_new_addr ()} /\ C12Zip_Zip_Type.zip_b ( * self) = C12Zip_Zip_Type.zip_b ( ^ self) \/ (exists x : Item0.item . Inv0.inv x /\ Produces0.produces (C12Zip_Zip_Type.zip_a ( * self)) (Seq.singleton x) (C12Zip_Zip_Type.zip_a ( ^ self)) /\ Resolve0.resolve x /\ Completed1.completed {current = C12Zip_Zip_Type.zip_b ( * self); final = C12Zip_Zip_Type.zip_b ( ^ self); addr = Borrow.make_new_addr ()})
+    [#"../12_zip.rs" 20 13 22 67] Completed0.completed {current = C12Zip_Zip_Type.zip_a ( * self); final = C12Zip_Zip_Type.zip_a ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1} /\ C12Zip_Zip_Type.zip_b ( * self) = C12Zip_Zip_Type.zip_b ( ^ self) \/ (exists x : Item0.item . Inv0.inv x /\ Produces0.produces (C12Zip_Zip_Type.zip_a ( * self)) (Seq.singleton x) (C12Zip_Zip_Type.zip_a ( ^ self)) /\ Resolve0.resolve x /\ Completed1.completed {current = C12Zip_Zip_Type.zip_b ( * self); final = C12Zip_Zip_Type.zip_b ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 2})
   val completed [#"../12_zip.rs" 18 4 18 35] (self : borrowed (C12Zip_Zip_Type.t_zip a b)) : bool
     ensures { result = completed self }
     
@@ -939,7 +939,7 @@ module C12Zip_Impl0_Next
     goto BB0
   }
   BB0 {
-    _5 <- Borrow.borrow_mut (C12Zip_Zip_Type.zip_a ( * self));
+    _5 <- Borrow.borrow_final (C12Zip_Zip_Type.zip_a ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C12Zip_Zip_Type.C_Zip a b =  * self in C12Zip_Zip_Type.C_Zip ( ^ _5) b) ; };
     assume { Inv0.inv ( ^ _5) };
     _4 <- ([#"../12_zip.rs" 55 22 55 35] Next0.next _5);
@@ -979,7 +979,7 @@ module C12Zip_Impl0_Next
     goto BB7
   }
   BB7 {
-    _11 <- Borrow.borrow_mut (C12Zip_Zip_Type.zip_b ( * self));
+    _11 <- Borrow.borrow_final (C12Zip_Zip_Type.zip_b ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let C12Zip_Zip_Type.C_Zip a b =  * self in C12Zip_Zip_Type.C_Zip a ( ^ _11)) ; };
     assume { Inv3.inv ( ^ _11) };
     _10 <- ([#"../12_zip.rs" 59 22 59 35] Next1.next _11);
diff --git a/creusot/tests/should_succeed/iterators/13_cloned.mlcfg b/creusot/tests/should_succeed/iterators/13_cloned.mlcfg
index a87989adc9..1f79729fa5 100644
--- a/creusot/tests/should_succeed/iterators/13_cloned.mlcfg
+++ b/creusot/tests/should_succeed/iterators/13_cloned.mlcfg
@@ -54,7 +54,7 @@ module C13Cloned_Impl0_Completed
     type self = i
   use C13Cloned_Cloned_Type as C13Cloned_Cloned_Type
   predicate completed [#"../13_cloned.rs" 22 4 22 35] (self : borrowed (C13Cloned_Cloned_Type.t_cloned i)) =
-    [#"../13_cloned.rs" 23 8 23 43] Completed0.completed {current = C13Cloned_Cloned_Type.cloned_iter ( * self); final = C13Cloned_Cloned_Type.cloned_iter ( ^ self); addr = Borrow.make_new_addr ()}
+    [#"../13_cloned.rs" 23 8 23 43] Completed0.completed {current = C13Cloned_Cloned_Type.cloned_iter ( * self); final = C13Cloned_Cloned_Type.cloned_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1}
   val completed [#"../13_cloned.rs" 22 4 22 35] (self : borrowed (C13Cloned_Cloned_Type.t_cloned i)) : bool
     ensures { result = completed self }
     
@@ -720,7 +720,7 @@ module C13Cloned_Impl0_Next
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut (C13Cloned_Cloned_Type.cloned_iter ( * self));
+    _4 <- Borrow.borrow_final (C13Cloned_Cloned_Type.cloned_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C13Cloned_Cloned_Type.C_Cloned a =  * self in C13Cloned_Cloned_Type.C_Cloned ( ^ _4)) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../13_cloned.rs" 53 8 53 24] Next0.next _4);
diff --git a/creusot/tests/should_succeed/iterators/14_copied.mlcfg b/creusot/tests/should_succeed/iterators/14_copied.mlcfg
index 9d8e21cbbb..c6636d1465 100644
--- a/creusot/tests/should_succeed/iterators/14_copied.mlcfg
+++ b/creusot/tests/should_succeed/iterators/14_copied.mlcfg
@@ -54,7 +54,7 @@ module C14Copied_Impl0_Completed
     type self = i
   use C14Copied_Copied_Type as C14Copied_Copied_Type
   predicate completed [#"../14_copied.rs" 22 4 22 35] (self : borrowed (C14Copied_Copied_Type.t_copied i)) =
-    [#"../14_copied.rs" 23 8 23 43] Completed0.completed {current = C14Copied_Copied_Type.copied_iter ( * self); final = C14Copied_Copied_Type.copied_iter ( ^ self); addr = Borrow.make_new_addr ()}
+    [#"../14_copied.rs" 23 8 23 43] Completed0.completed {current = C14Copied_Copied_Type.copied_iter ( * self); final = C14Copied_Copied_Type.copied_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1}
   val completed [#"../14_copied.rs" 22 4 22 35] (self : borrowed (C14Copied_Copied_Type.t_copied i)) : bool
     ensures { result = completed self }
     
@@ -720,7 +720,7 @@ module C14Copied_Impl0_Next
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut (C14Copied_Copied_Type.copied_iter ( * self));
+    _4 <- Borrow.borrow_final (C14Copied_Copied_Type.copied_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C14Copied_Copied_Type.C_Copied a =  * self in C14Copied_Copied_Type.C_Copied ( ^ _4)) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../14_copied.rs" 53 8 53 24] Next0.next _4);
diff --git a/creusot/tests/should_succeed/iterators/15_enumerate.mlcfg b/creusot/tests/should_succeed/iterators/15_enumerate.mlcfg
index 988f3a1ce5..39f76224e1 100644
--- a/creusot/tests/should_succeed/iterators/15_enumerate.mlcfg
+++ b/creusot/tests/should_succeed/iterators/15_enumerate.mlcfg
@@ -57,7 +57,7 @@ module C15Enumerate_Impl0_Completed
     type self = i
   use C15Enumerate_Enumerate_Type as C15Enumerate_Enumerate_Type
   predicate completed [#"../15_enumerate.rs" 22 4 22 35] (self : borrowed (C15Enumerate_Enumerate_Type.t_enumerate i)) =
-    [#"../15_enumerate.rs" 23 8 23 43] Completed0.completed {current = C15Enumerate_Enumerate_Type.enumerate_iter ( * self); final = C15Enumerate_Enumerate_Type.enumerate_iter ( ^ self); addr = Borrow.make_new_addr ()}
+    [#"../15_enumerate.rs" 23 8 23 43] Completed0.completed {current = C15Enumerate_Enumerate_Type.enumerate_iter ( * self); final = C15Enumerate_Enumerate_Type.enumerate_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1}
   val completed [#"../15_enumerate.rs" 22 4 22 35] (self : borrowed (C15Enumerate_Enumerate_Type.t_enumerate i)) : bool
     ensures { result = completed self }
     
@@ -880,7 +880,7 @@ module C15Enumerate_Impl0_Next
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut (C15Enumerate_Enumerate_Type.enumerate_iter ( * self));
+    _4 <- Borrow.borrow_final (C15Enumerate_Enumerate_Type.enumerate_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C15Enumerate_Enumerate_Type.C_Enumerate a b =  * self in C15Enumerate_Enumerate_Type.C_Enumerate ( ^ _4) b) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../15_enumerate.rs" 54 14 54 30] Next0.next _4);
diff --git a/creusot/tests/should_succeed/iterators/16_take.mlcfg b/creusot/tests/should_succeed/iterators/16_take.mlcfg
index 4ae224be05..92f9e93e32 100644
--- a/creusot/tests/should_succeed/iterators/16_take.mlcfg
+++ b/creusot/tests/should_succeed/iterators/16_take.mlcfg
@@ -83,7 +83,7 @@ module C16Take_Impl0_Completed
   clone CreusotContracts_Resolve_Impl1_Resolve_Stub as Resolve0 with
     type t = C16Take_Take_Type.t_take i
   predicate completed [#"../16_take.rs" 22 4 22 35] (self : borrowed (C16Take_Take_Type.t_take i)) =
-    [#"../16_take.rs" 23 8 26 9] UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) = 0 /\ Resolve0.resolve self \/ UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) > 0 /\ UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) = UIntSize.to_int (C16Take_Take_Type.take_n ( ^ self)) + 1 /\ Completed0.completed {current = C16Take_Take_Type.take_iter ( * self); final = C16Take_Take_Type.take_iter ( ^ self); addr = Borrow.make_new_addr ()}
+    [#"../16_take.rs" 23 8 26 9] UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) = 0 /\ Resolve0.resolve self \/ UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) > 0 /\ UIntSize.to_int (C16Take_Take_Type.take_n ( * self)) = UIntSize.to_int (C16Take_Take_Type.take_n ( ^ self)) + 1 /\ Completed0.completed {current = C16Take_Take_Type.take_iter ( * self); final = C16Take_Take_Type.take_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1}
   val completed [#"../16_take.rs" 22 4 22 35] (self : borrowed (C16Take_Take_Type.t_take i)) : bool
     ensures { result = completed self }
     
@@ -699,7 +699,7 @@ module C16Take_Impl0_Next
   }
   BB1 {
     self <- { self with current = (let C16Take_Take_Type.C_Take a b =  * self in C16Take_Take_Type.C_Take a ([#"../16_take.rs" 55 12 55 23] C16Take_Take_Type.take_n ( * self) - ([#"../16_take.rs" 55 22 55 23] (1 : usize)))) ; };
-    _5 <- Borrow.borrow_mut (C16Take_Take_Type.take_iter ( * self));
+    _5 <- Borrow.borrow_final (C16Take_Take_Type.take_iter ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let C16Take_Take_Type.C_Take a b =  * self in C16Take_Take_Type.C_Take ( ^ _5) b) ; };
     assume { Inv1.inv ( ^ _5) };
     _0 <- ([#"../16_take.rs" 56 12 56 28] Next0.next _5);
diff --git a/creusot/tests/should_succeed/knapsack_full.mlcfg b/creusot/tests/should_succeed/knapsack_full.mlcfg
index 11ccbb7fa7..9f8af046a8 100644
--- a/creusot/tests/should_succeed/knapsack_full.mlcfg
+++ b/creusot/tests/should_succeed/knapsack_full.mlcfg
@@ -3008,7 +3008,7 @@ module KnapsackFull_Knapsack01Dyn
   BB13 {
     _34 <- Borrow.borrow_mut iter;
     iter <-  ^ _34;
-    _33 <- Borrow.borrow_mut ( * _34);
+    _33 <- Borrow.borrow_final ( * _34) (Borrow.get_id _34);
     _34 <- { _34 with current = ( ^ _33) ; };
     _32 <- ([#"../knapsack_full.rs" 88 4 88 55] Next0.next _33);
     _33 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
@@ -3094,7 +3094,7 @@ module KnapsackFull_Knapsack01Dyn
   BB31 {
     _60 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _60;
-    _59 <- Borrow.borrow_mut ( * _60);
+    _59 <- Borrow.borrow_final ( * _60) (Borrow.get_id _60);
     _60 <- { _60 with current = ( ^ _59) ; };
     _58 <- ([#"../knapsack_full.rs" 98 8 98 59] Next1.next _59);
     _59 <- any borrowed (Core_Ops_Range_RangeInclusive_Type.t_rangeinclusive usize);
diff --git a/creusot/tests/should_succeed/lang/branch_borrow_2.mlcfg b/creusot/tests/should_succeed/lang/branch_borrow_2.mlcfg
index 800215a910..8a253a0e64 100644
--- a/creusot/tests/should_succeed/lang/branch_borrow_2.mlcfg
+++ b/creusot/tests/should_succeed/lang/branch_borrow_2.mlcfg
@@ -72,7 +72,7 @@ module BranchBorrow2_F
   }
   BB3 {
     z <- { z with current = ([#"../branch_borrow_2.rs" 23 17 23 18] (8 : int32)) ; };
-    _12 <- Borrow.borrow_mut ( * z);
+    _12 <- Borrow.borrow_final ( * z) (Borrow.get_id z);
     z <- { z with current = ( ^ _12) ; };
     w <- _12;
     _12 <- any borrowed int32;
@@ -91,7 +91,7 @@ module BranchBorrow2_F
   BB5 {
     assume { Resolve0.resolve z };
     y <- { y with current = ([#"../branch_borrow_2.rs" 19 17 19 18] (7 : int32)) ; };
-    _11 <- Borrow.borrow_mut ( * y);
+    _11 <- Borrow.borrow_final ( * y) (Borrow.get_id y);
     y <- { y with current = ( ^ _11) ; };
     w <- _11;
     _11 <- any borrowed int32;
@@ -237,9 +237,9 @@ module BranchBorrow2_G
     a <- (BranchBorrow2_MyInt_Type.C_MyInt ([#"../branch_borrow_2.rs" 36 23 36 25] (10 : usize)), BranchBorrow2_MyInt_Type.C_MyInt ([#"../branch_borrow_2.rs" 36 34 36 35] (5 : usize)));
     b <- Borrow.borrow_mut a;
     a <-  ^ b;
-    c <- Borrow.borrow_mut (let (_, a) =  * b in a);
+    c <- Borrow.borrow_final (let (_, a) =  * b in a) (Borrow.inherit_id (Borrow.get_id b) 2);
     b <- { b with current = (let (a, b) =  * b in (a,  ^ c)) ; };
-    d <- Borrow.borrow_mut (let (a, _) =  * b in a);
+    d <- Borrow.borrow_final (let (a, _) =  * b in a) (Borrow.inherit_id (Borrow.get_id b) 1);
     b <- { b with current = (let (a, b) =  * b in ( ^ d, b)) ; };
     assume { Resolve0.resolve c };
     assume { Resolve0.resolve d };
@@ -295,7 +295,7 @@ module BranchBorrow2_H
   BB2 {
     assume { Resolve0.resolve x };
     y <- { y with current = ([#"../branch_borrow_2.rs" 56 13 56 14] (6 : int32)) ; };
-    _9 <- Borrow.borrow_mut ( * y);
+    _9 <- Borrow.borrow_final ( * y) (Borrow.get_id y);
     y <- { y with current = ( ^ _9) ; };
     w <- _9;
     _9 <- any borrowed int32;
diff --git a/creusot/tests/should_succeed/list_index_mut.mlcfg b/creusot/tests/should_succeed/list_index_mut.mlcfg
index 4bad397ee2..150b52e979 100644
--- a/creusot/tests/should_succeed/list_index_mut.mlcfg
+++ b/creusot/tests/should_succeed/list_index_mut.mlcfg
@@ -394,7 +394,7 @@ module ListIndexMut_IndexMut
       end
   }
   BB5 {
-    _25 <- Borrow.borrow_mut (ListIndexMut_List_Type.list_1 ( * l));
+    _25 <- Borrow.borrow_final (ListIndexMut_List_Type.list_1 ( * l)) (Borrow.inherit_id (Borrow.get_id l) 2);
     l <- { l with current = (let ListIndexMut_List_Type.C_List a b =  * l in ListIndexMut_List_Type.C_List a ( ^ _25)) ; };
     _24 <- ([#"../list_index_mut.rs" 50 12 50 24] AsMut0.as_mut _25);
     _25 <- any borrowed (Core_Option_Option_Type.t_option (ListIndexMut_List_Type.t_list));
@@ -416,11 +416,11 @@ module ListIndexMut_IndexMut
     goto BB3
   }
   BB8 {
-    _29 <- Borrow.borrow_mut (ListIndexMut_List_Type.list_0 ( * l));
+    _29 <- Borrow.borrow_final (ListIndexMut_List_Type.list_0 ( * l)) (Borrow.inherit_id (Borrow.get_id l) 1);
     l <- { l with current = (let ListIndexMut_List_Type.C_List a b =  * l in ListIndexMut_List_Type.C_List ( ^ _29) b) ; };
-    _3 <- Borrow.borrow_mut ( * _29);
+    _3 <- Borrow.borrow_final ( * _29) (Borrow.get_id _29);
     _29 <- { _29 with current = ( ^ _3) ; };
-    _0 <- Borrow.borrow_mut ( * _3);
+    _0 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _29 };
     assume { Resolve0.resolve _3 };
@@ -478,7 +478,7 @@ module ListIndexMut_Write
     goto BB0
   }
   BB0 {
-    _10 <- Borrow.borrow_mut ( * l);
+    _10 <- Borrow.borrow_final ( * l) (Borrow.get_id l);
     l <- { l with current = ( ^ _10) ; };
     _9 <- ([#"../list_index_mut.rs" 64 5 64 21] IndexMut0.index_mut _10 ix);
     _10 <- any borrowed (ListIndexMut_List_Type.t_list);
@@ -536,7 +536,7 @@ module ListIndexMut_F
   BB4 {
     _8 <- Borrow.borrow_mut l;
     l <-  ^ _8;
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     _6 <- ([#"../list_index_mut.rs" 69 4 69 23] Write0.write _7 ([#"../list_index_mut.rs" 69 18 69 19] (0 : usize)) ([#"../list_index_mut.rs" 69 21 69 22] (2 : uint32)));
     _7 <- any borrowed (ListIndexMut_List_Type.t_list);
diff --git a/creusot/tests/should_succeed/list_reversal_lasso.mlcfg b/creusot/tests/should_succeed/list_reversal_lasso.mlcfg
index 624f174662..1d4f28562d 100644
--- a/creusot/tests/should_succeed/list_reversal_lasso.mlcfg
+++ b/creusot/tests/should_succeed/list_reversal_lasso.mlcfg
@@ -928,18 +928,18 @@ module ListReversalLasso_Impl2_IndexMut
     goto BB0
   }
   BB0 {
-    _11 <- Borrow.borrow_mut (ListReversalLasso_Memory_Type.memory_0 ( * self));
+    _11 <- Borrow.borrow_final (ListReversalLasso_Memory_Type.memory_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let ListReversalLasso_Memory_Type.C_Memory a =  * self in ListReversalLasso_Memory_Type.C_Memory ( ^ _11)) ; };
     _10 <- ([#"../list_reversal_lasso.rs" 42 13 42 22] IndexMut0.index_mut _11 i);
     _11 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
     goto BB1
   }
   BB1 {
-    _9 <- Borrow.borrow_mut ( * _10);
+    _9 <- Borrow.borrow_final ( * _10) (Borrow.get_id _10);
     _10 <- { _10 with current = ( ^ _9) ; };
-    _3 <- Borrow.borrow_mut ( * _9);
+    _3 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _3) ; };
-    _0 <- Borrow.borrow_mut ( * _3);
+    _0 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _10 };
     assume { Resolve0.resolve _9 };
@@ -1344,11 +1344,11 @@ module ListReversalLasso_Impl4_ListReversalList
   BB5 {
     _19 <- Borrow.borrow_mut ( * _20);
     _20 <- { _20 with current = ( ^ _19) ; };
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _25 <- Borrow.borrow_mut r;
     r <-  ^ _25;
-    _24 <- Borrow.borrow_mut ( * _25);
+    _24 <- Borrow.borrow_final ( * _25) (Borrow.get_id _25);
     _25 <- { _25 with current = ( ^ _24) ; };
     _23 <- ([#"../list_reversal_lasso.rs" 108 48 108 76] Replace0.replace _24 l);
     _24 <- any borrowed usize;
@@ -1597,11 +1597,11 @@ module ListReversalLasso_Impl4_ListReversalLoop
   BB5 {
     _23 <- Borrow.borrow_mut ( * _24);
     _24 <- { _24 with current = ( ^ _23) ; };
-    _22 <- Borrow.borrow_mut ( * _23);
+    _22 <- Borrow.borrow_final ( * _23) (Borrow.get_id _23);
     _23 <- { _23 with current = ( ^ _22) ; };
     _29 <- Borrow.borrow_mut r;
     r <-  ^ _29;
-    _28 <- Borrow.borrow_mut ( * _29);
+    _28 <- Borrow.borrow_final ( * _29) (Borrow.get_id _29);
     _29 <- { _29 with current = ( ^ _28) ; };
     _27 <- ([#"../list_reversal_lasso.rs" 139 48 139 76] Replace0.replace _28 l);
     _28 <- any borrowed usize;
@@ -1833,11 +1833,11 @@ module ListReversalLasso_Impl4_ListReversalLasso
   BB5 {
     _21 <- Borrow.borrow_mut ( * _22);
     _22 <- { _22 with current = ( ^ _21) ; };
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     _27 <- Borrow.borrow_mut r;
     r <-  ^ _27;
-    _26 <- Borrow.borrow_mut ( * _27);
+    _26 <- Borrow.borrow_final ( * _27) (Borrow.get_id _27);
     _27 <- { _27 with current = ( ^ _26) ; };
     _25 <- ([#"../list_reversal_lasso.rs" 191 48 191 76] Replace0.replace _26 l);
     _26 <- any borrowed usize;
diff --git a/creusot/tests/should_succeed/mapping_test.mlcfg b/creusot/tests/should_succeed/mapping_test.mlcfg
index 661f595f43..b41d30c143 100644
--- a/creusot/tests/should_succeed/mapping_test.mlcfg
+++ b/creusot/tests/should_succeed/mapping_test.mlcfg
@@ -307,7 +307,7 @@ module MappingTest_F
     assert { [@expl:assertion] [#"../mapping_test.rs" 41 19 41 34] Map.get (ShallowModel0.shallow_model x) 42 = 0 };
     _8 <- Borrow.borrow_mut x;
     x <-  ^ _8;
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     _6 <- ([#"../mapping_test.rs" 42 4 42 16] Incr0.incr _7);
     _7 <- any borrowed (MappingTest_T_Type.t_t);
diff --git a/creusot/tests/should_succeed/projection_toggle.mlcfg b/creusot/tests/should_succeed/projection_toggle.mlcfg
index efbe623557..1ca317bd9b 100644
--- a/creusot/tests/should_succeed/projection_toggle.mlcfg
+++ b/creusot/tests/should_succeed/projection_toggle.mlcfg
@@ -109,10 +109,10 @@ module ProjectionToggle_ProjToggle
   BB1 {
     assert { [@expl:type invariant] Inv0.inv b };
     assume { Resolve0.resolve b };
-    _8 <- Borrow.borrow_mut ( * a);
+    _8 <- Borrow.borrow_final ( * a) (Borrow.get_id a);
     a <- { a with current = ( ^ _8) ; };
     assume { Inv1.inv ( ^ _8) };
-    _6 <- Borrow.borrow_mut ( * _8);
+    _6 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _6) ; };
     assume { Inv1.inv ( ^ _6) };
     assert { [@expl:type invariant] Inv0.inv _8 };
@@ -122,16 +122,16 @@ module ProjectionToggle_ProjToggle
   BB2 {
     assert { [@expl:type invariant] Inv0.inv a };
     assume { Resolve0.resolve a };
-    _6 <- Borrow.borrow_mut ( * b);
+    _6 <- Borrow.borrow_final ( * b) (Borrow.get_id b);
     b <- { b with current = ( ^ _6) ; };
     assume { Inv1.inv ( ^ _6) };
     goto BB3
   }
   BB3 {
-    _4 <- Borrow.borrow_mut ( * _6);
+    _4 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _4) ; };
     assume { Inv1.inv ( ^ _4) };
-    _0 <- Borrow.borrow_mut ( * _4);
+    _0 <- Borrow.borrow_final ( * _4) (Borrow.get_id _4);
     _4 <- { _4 with current = ( ^ _0) ; };
     assume { Inv1.inv ( ^ _0) };
     assert { [@expl:type invariant] Inv0.inv _6 };
@@ -182,11 +182,11 @@ module ProjectionToggle_F
     b <- ([#"../projection_toggle.rs" 15 16 15 17] (5 : int32));
     _5 <- Borrow.borrow_mut a;
     a <-  ^ _5;
-    _4 <- Borrow.borrow_mut ( * _5);
+    _4 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _4) ; };
     _7 <- Borrow.borrow_mut b;
     b <-  ^ _7;
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     x <- ([#"../projection_toggle.rs" 17 12 17 45] ProjToggle0.proj_toggle ([#"../projection_toggle.rs" 17 24 17 28] true) _4 _6);
     _4 <- any borrowed int32;
diff --git a/creusot/tests/should_succeed/projections.mlcfg b/creusot/tests/should_succeed/projections.mlcfg
index 0c9e7562ef..4c9745c702 100644
--- a/creusot/tests/should_succeed/projections.mlcfg
+++ b/creusot/tests/should_succeed/projections.mlcfg
@@ -172,7 +172,7 @@ module Projections_WriteIntoSum
     absurd
   }
   BB4 {
-    y <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * x));
+    y <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * x)) (Borrow.inherit_id (Borrow.get_id x) 1);
     x <- { x with current = (let Core_Option_Option_Type.C_Some a =  * x in Core_Option_Option_Type.C_Some ( ^ y)) ; };
     y <- { y with current = ([#"../projections.rs" 18 24 18 26] (10 : uint32)) ; };
     assume { Resolve0.resolve y };
diff --git a/creusot/tests/should_succeed/red_black_tree.mlcfg b/creusot/tests/should_succeed/red_black_tree.mlcfg
index bf8d609f47..ebde59d614 100644
--- a/creusot/tests/should_succeed/red_black_tree.mlcfg
+++ b/creusot/tests/should_succeed/red_black_tree.mlcfg
@@ -3469,7 +3469,7 @@ module RedBlackTree_Impl14_RotateRight
     _16 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_left ( * self)));
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_left ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _16)) b c d e) ; };
     assume { Inv1.inv ( ^ _16) };
-    _15 <- Borrow.borrow_mut ( * _16);
+    _15 <- Borrow.borrow_final ( * _16) (Borrow.get_id _16);
     _16 <- { _16 with current = ( ^ _15) ; };
     assume { Inv1.inv ( ^ _15) };
     _14 <- ([#"../red_black_tree.rs" 421 20 421 55] Take0.take _15);
@@ -3487,13 +3487,13 @@ module RedBlackTree_Impl14_RotateRight
     _19 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_left ( * self));
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node ( ^ _19) b c d e) ; };
     assume { Inv3.inv ( ^ _19) };
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     assume { Inv3.inv ( ^ _18) };
     _21 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_right x);
     x <- (let RedBlackTree_Node_Type.C_Node a b c d e = x in RedBlackTree_Node_Type.C_Node a b c d ( ^ _21));
     assume { Inv3.inv ( ^ _21) };
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     assume { Inv3.inv ( ^ _20) };
     _17 <- ([#"../red_black_tree.rs" 428 8 428 52] Swap0.swap _18 _20);
@@ -3523,13 +3523,13 @@ module RedBlackTree_Impl14_RotateRight
   BB5 {
     assert { [@expl:type invariant] Inv7.inv _25 };
     assume { Resolve3.resolve _25 };
-    _28 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color ( * self));
+    _28 <- Borrow.borrow_final (RedBlackTree_Node_Type.node_color ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a ( ^ _28) c d e) ; };
-    _27 <- Borrow.borrow_mut ( * _28);
+    _27 <- Borrow.borrow_final ( * _28) (Borrow.get_id _28);
     _28 <- { _28 with current = ( ^ _27) ; };
     _30 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color x);
     x <- (let RedBlackTree_Node_Type.C_Node a b c d e = x in RedBlackTree_Node_Type.C_Node a ( ^ _30) c d e);
-    _29 <- Borrow.borrow_mut ( * _30);
+    _29 <- Borrow.borrow_final ( * _30) (Borrow.get_id _30);
     _30 <- { _30 with current = ( ^ _29) ; };
     _26 <- ([#"../red_black_tree.rs" 435 8 435 53] Swap2.swap _27 _29);
     _27 <- any borrowed (RedBlackTree_Color_Type.t_color);
@@ -3932,7 +3932,7 @@ module RedBlackTree_Impl14_RotateLeft
     _16 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_right ( * self)));
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a b c d (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_right ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _16))) ; };
     assume { Inv1.inv ( ^ _16) };
-    _15 <- Borrow.borrow_mut ( * _16);
+    _15 <- Borrow.borrow_final ( * _16) (Borrow.get_id _16);
     _16 <- { _16 with current = ( ^ _15) ; };
     assume { Inv1.inv ( ^ _15) };
     _14 <- ([#"../red_black_tree.rs" 464 20 464 56] Take0.take _15);
@@ -3950,13 +3950,13 @@ module RedBlackTree_Impl14_RotateLeft
     _19 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_right ( * self));
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a b c d ( ^ _19)) ; };
     assume { Inv3.inv ( ^ _19) };
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     assume { Inv3.inv ( ^ _18) };
     _21 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_left x);
     x <- (let RedBlackTree_Node_Type.C_Node a b c d e = x in RedBlackTree_Node_Type.C_Node ( ^ _21) b c d e);
     assume { Inv3.inv ( ^ _21) };
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     assume { Inv3.inv ( ^ _20) };
     _17 <- ([#"../red_black_tree.rs" 465 8 465 52] Swap0.swap _18 _20);
@@ -3986,13 +3986,13 @@ module RedBlackTree_Impl14_RotateLeft
   BB5 {
     assert { [@expl:type invariant] Inv7.inv _25 };
     assume { Resolve3.resolve _25 };
-    _28 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color ( * self));
+    _28 <- Borrow.borrow_final (RedBlackTree_Node_Type.node_color ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a ( ^ _28) c d e) ; };
-    _27 <- Borrow.borrow_mut ( * _28);
+    _27 <- Borrow.borrow_final ( * _28) (Borrow.get_id _28);
     _28 <- { _28 with current = ( ^ _27) ; };
     _30 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color x);
     x <- (let RedBlackTree_Node_Type.C_Node a b c d e = x in RedBlackTree_Node_Type.C_Node a ( ^ _30) c d e);
-    _29 <- Borrow.borrow_mut ( * _30);
+    _29 <- Borrow.borrow_final ( * _30) (Borrow.get_id _30);
     _30 <- { _30 with current = ( ^ _29) ; };
     _26 <- ([#"../red_black_tree.rs" 467 8 467 53] Swap2.swap _27 _29);
     _27 <- any borrowed (RedBlackTree_Color_Type.t_color);
@@ -4366,7 +4366,7 @@ module RedBlackTree_Impl14_FlipColors
     goto BB0
   }
   BB0 {
-    _15 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_left ( * self)));
+    _15 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_left ( * self))) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id self) 1) 1);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_left ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _15)) b c d e) ; };
     assume { Inv0.inv ( ^ _15) };
     _14 <- ([#"../red_black_tree.rs" 487 8 487 31] AsMut0.as_mut _15);
@@ -4382,11 +4382,11 @@ module RedBlackTree_Impl14_FlipColors
     _13 <- { _13 with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * _13 in RedBlackTree_Node_Type.C_Node a (RedBlackTree_Node_Type.node_color ( * self)) c d e) ; };
     assert { [@expl:type invariant] Inv1.inv _13 };
     assume { Resolve0.resolve _13 };
-    _18 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color ( * self));
+    _18 <- Borrow.borrow_final (RedBlackTree_Node_Type.node_color ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a ( ^ _18) c d e) ; };
-    _17 <- Borrow.borrow_mut ( * _18);
+    _17 <- Borrow.borrow_final ( * _18) (Borrow.get_id _18);
     _18 <- { _18 with current = ( ^ _17) ; };
-    _23 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_right ( * self)));
+    _23 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_right ( * self))) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id self) 5) 1);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a b c d (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_right ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _23))) ; };
     assume { Inv0.inv ( ^ _23) };
     _22 <- ([#"../red_black_tree.rs" 488 45 488 69] AsMut0.as_mut _23);
@@ -4401,7 +4401,7 @@ module RedBlackTree_Impl14_FlipColors
   BB4 {
     _20 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_color ( * _21));
     _21 <- { _21 with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * _21 in RedBlackTree_Node_Type.C_Node a ( ^ _20) c d e) ; };
-    _19 <- Borrow.borrow_mut ( * _20);
+    _19 <- Borrow.borrow_final ( * _20) (Borrow.get_id _20);
     _20 <- { _20 with current = ( ^ _19) ; };
     _16 <- ([#"../red_black_tree.rs" 488 8 488 85] Swap0.swap _17 _19);
     _17 <- any borrowed (RedBlackTree_Color_Type.t_color);
@@ -4969,7 +4969,7 @@ module RedBlackTree_Impl14_Balance
     goto BB23
   }
   BB26 {
-    _40 <- Borrow.borrow_mut ( * self);
+    _40 <- Borrow.borrow_final ( * self) (Borrow.get_id self);
     self <- { self with current = ( ^ _40) ; };
     assume { Inv0.inv ( ^ _40) };
     _39 <- ([#"../red_black_tree.rs" 520 12 520 30] FlipColors0.flip_colors _40);
@@ -5496,7 +5496,7 @@ module RedBlackTree_Impl14_MoveRedLeft
     goto BB10
   }
   BB10 {
-    _35 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_left ( * self)));
+    _35 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_left ( * self))) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id self) 1) 1);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_left ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _35)) b c d e) ; };
     assume { Inv1.inv ( ^ _35) };
     _34 <- ([#"../red_black_tree.rs" 548 19 548 42] AsMut0.as_mut _35);
@@ -5991,7 +5991,7 @@ module RedBlackTree_Impl14_MoveRedRight
     goto BB7
   }
   BB7 {
-    _30 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_right ( * self)));
+    _30 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node (RedBlackTree_Node_Type.node_right ( * self))) (Borrow.inherit_id (Borrow.inherit_id (Borrow.get_id self) 5) 1);
     self <- { self with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * self in RedBlackTree_Node_Type.C_Node a b c d (let RedBlackTree_Tree_Type.C_Tree a = RedBlackTree_Node_Type.node_right ( * self) in RedBlackTree_Tree_Type.C_Tree ( ^ _30))) ; };
     assume { Inv1.inv ( ^ _30) };
     _29 <- ([#"../red_black_tree.rs" 576 19 576 43] AsMut0.as_mut _30);
@@ -6626,7 +6626,7 @@ module RedBlackTree_Impl15_InsertRec
     goto BB2
   }
   BB2 {
-    _11 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _11 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _11)) ; };
     assume { Inv0.inv ( ^ _11) };
     switch ( * _11)
@@ -6638,7 +6638,7 @@ module RedBlackTree_Impl15_InsertRec
     goto BB4
   }
   BB4 {
-    node <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _11));
+    node <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _11)) (Borrow.inherit_id (Borrow.get_id _11) 1);
     _11 <- { _11 with current = (let Core_Option_Option_Type.C_Some a =  * _11 in Core_Option_Option_Type.C_Some ( ^ node)) ; };
     assume { Inv1.inv ( ^ node) };
     _18 <- RedBlackTree_Node_Type.node_key ( * node);
@@ -7222,7 +7222,7 @@ module RedBlackTree_Impl15_Insert
     goto BB2
   }
   BB2 {
-    _14 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _14 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _14)) ; };
     assume { Inv1.inv ( ^ _14) };
     _13 <- ([#"../red_black_tree.rs" 628 8 628 26] AsMut0.as_mut _14);
@@ -7771,7 +7771,7 @@ module RedBlackTree_Impl15_DeleteMaxRec
     goto BB2
   }
   BB2 {
-    _12 <- Borrow.borrow_mut ( * _13);
+    _12 <- Borrow.borrow_final ( * _13) (Borrow.get_id _13);
     _13 <- { _13 with current = ( ^ _12) ; };
     assume { Inv1.inv ( ^ _12) };
     node <- ([#"../red_black_tree.rs" 644 23 644 59] AsMut1.as_mut _12);
@@ -7817,10 +7817,10 @@ module RedBlackTree_Impl15_DeleteMaxRec
   BB10 {
     assert { [@expl:type invariant] Inv4.inv node };
     assume { Resolve1.resolve node };
-    _26 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _26 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _26)) ; };
     assume { Inv0.inv ( ^ _26) };
-    _25 <- Borrow.borrow_mut ( * _26);
+    _25 <- Borrow.borrow_final ( * _26) (Borrow.get_id _26);
     _26 <- { _26 with current = ( ^ _25) ; };
     assume { Inv0.inv ( ^ _25) };
     _24 <- ([#"../red_black_tree.rs" 649 23 649 53] Take0.take _25);
@@ -7891,7 +7891,7 @@ module RedBlackTree_Impl15_DeleteMaxRec
     goto BB18
   }
   BB23 {
-    _42 <- Borrow.borrow_mut ( * node);
+    _42 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _42) ; };
     assume { Inv3.inv ( ^ _42) };
     _41 <- ([#"../red_black_tree.rs" 653 19 653 40] MoveRedRight0.move_red_right _42);
@@ -7899,7 +7899,7 @@ module RedBlackTree_Impl15_DeleteMaxRec
     goto BB24
   }
   BB24 {
-    _40 <- Borrow.borrow_mut ( * _41);
+    _40 <- Borrow.borrow_final ( * _41) (Borrow.get_id _41);
     _41 <- { _41 with current = ( ^ _40) ; };
     assume { Inv3.inv ( ^ _40) };
     assert { [@expl:type invariant] Inv4.inv node };
@@ -7924,7 +7924,7 @@ module RedBlackTree_Impl15_DeleteMaxRec
     goto BB27
   }
   BB27 {
-    _46 <- Borrow.borrow_mut ( * node);
+    _46 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _46) ; };
     assume { Inv3.inv ( ^ _46) };
     _45 <- ([#"../red_black_tree.rs" 656 8 656 22] Balance0.balance _46);
@@ -8371,7 +8371,7 @@ module RedBlackTree_Impl15_DeleteMax
     goto BB3
   }
   BB3 {
-    node <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _8));
+    node <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _8)) (Borrow.inherit_id (Borrow.get_id _8) 1);
     _8 <- { _8 with current = (let Core_Option_Option_Type.C_Some a =  * _8 in Core_Option_Option_Type.C_Some ( ^ node)) ; };
     assume { Inv2.inv ( ^ node) };
     _12 <- ([#"../red_black_tree.rs" 670 16 670 34] IsRed0.is_red (RedBlackTree_Node_Type.node_left ( * node)));
@@ -8428,7 +8428,7 @@ module RedBlackTree_Impl15_DeleteMax
       end
   }
   BB11 {
-    _26 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _26 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _26)) ; };
     assume { Inv1.inv ( ^ _26) };
     _25 <- ([#"../red_black_tree.rs" 679 12 679 30] AsMut0.as_mut _26);
@@ -8958,7 +8958,7 @@ module RedBlackTree_Impl15_DeleteMinRec
     goto BB2
   }
   BB2 {
-    _12 <- Borrow.borrow_mut ( * _13);
+    _12 <- Borrow.borrow_final ( * _13) (Borrow.get_id _13);
     _13 <- { _13 with current = ( ^ _12) ; };
     assume { Inv1.inv ( ^ _12) };
     node <- ([#"../red_black_tree.rs" 697 23 697 59] AsMut1.as_mut _12);
@@ -8979,10 +8979,10 @@ module RedBlackTree_Impl15_DeleteMinRec
   BB5 {
     assert { [@expl:type invariant] Inv3.inv node };
     assume { Resolve1.resolve node };
-    _22 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _22 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _22)) ; };
     assume { Inv0.inv ( ^ _22) };
-    _21 <- Borrow.borrow_mut ( * _22);
+    _21 <- Borrow.borrow_final ( * _22) (Borrow.get_id _22);
     _22 <- { _22 with current = ( ^ _21) ; };
     assume { Inv0.inv ( ^ _21) };
     _20 <- ([#"../red_black_tree.rs" 699 23 699 53] Take0.take _21);
@@ -9053,7 +9053,7 @@ module RedBlackTree_Impl15_DeleteMinRec
     goto BB13
   }
   BB18 {
-    _38 <- Borrow.borrow_mut ( * node);
+    _38 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _38) ; };
     assume { Inv7.inv ( ^ _38) };
     _37 <- ([#"../red_black_tree.rs" 703 19 703 39] MoveRedLeft0.move_red_left _38);
@@ -9061,7 +9061,7 @@ module RedBlackTree_Impl15_DeleteMinRec
     goto BB19
   }
   BB19 {
-    _36 <- Borrow.borrow_mut ( * _37);
+    _36 <- Borrow.borrow_final ( * _37) (Borrow.get_id _37);
     _37 <- { _37 with current = ( ^ _36) ; };
     assume { Inv7.inv ( ^ _36) };
     assert { [@expl:type invariant] Inv3.inv node };
@@ -9086,7 +9086,7 @@ module RedBlackTree_Impl15_DeleteMinRec
     goto BB22
   }
   BB22 {
-    _42 <- Borrow.borrow_mut ( * node);
+    _42 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _42) ; };
     assume { Inv7.inv ( ^ _42) };
     _41 <- ([#"../red_black_tree.rs" 706 8 706 22] Balance0.balance _42);
@@ -9516,7 +9516,7 @@ module RedBlackTree_Impl15_DeleteMin
     goto BB3
   }
   BB3 {
-    node <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _8));
+    node <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _8)) (Borrow.inherit_id (Borrow.get_id _8) 1);
     _8 <- { _8 with current = (let Core_Option_Option_Type.C_Some a =  * _8 in Core_Option_Option_Type.C_Some ( ^ node)) ; };
     assume { Inv1.inv ( ^ node) };
     _12 <- ([#"../red_black_tree.rs" 723 16 723 34] IsRed0.is_red (RedBlackTree_Node_Type.node_left ( * node)));
@@ -9572,7 +9572,7 @@ module RedBlackTree_Impl15_DeleteMin
       end
   }
   BB11 {
-    _24 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _24 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _24)) ; };
     assume { Inv0.inv ( ^ _24) };
     _23 <- ([#"../red_black_tree.rs" 731 12 731 30] AsMut0.as_mut _24);
@@ -10368,7 +10368,7 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB2
   }
   BB2 {
-    _13 <- Borrow.borrow_mut ( * _14);
+    _13 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _13) ; };
     assume { Inv1.inv ( ^ _13) };
     node <- ([#"../red_black_tree.rs" 750 23 750 59] AsMut1.as_mut _13);
@@ -10459,7 +10459,7 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB13
   }
   BB18 {
-    _40 <- Borrow.borrow_mut ( * node);
+    _40 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _40) ; };
     assume { Inv5.inv ( ^ _40) };
     _39 <- ([#"../red_black_tree.rs" 757 27 757 47] MoveRedLeft0.move_red_left _40);
@@ -10467,7 +10467,7 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB19
   }
   BB19 {
-    _38 <- Borrow.borrow_mut ( * _39);
+    _38 <- Borrow.borrow_final ( * _39) (Borrow.get_id _39);
     _39 <- { _39 with current = ( ^ _38) ; };
     assume { Inv5.inv ( ^ _38) };
     assert { [@expl:type invariant] Inv6.inv node };
@@ -10571,10 +10571,10 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB73
   }
   BB38 {
-    _62 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _62 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _62)) ; };
     assume { Inv0.inv ( ^ _62) };
-    _61 <- Borrow.borrow_mut ( * _62);
+    _61 <- Borrow.borrow_final ( * _62) (Borrow.get_id _62);
     _62 <- { _62 with current = ( ^ _61) ; };
     assume { Inv0.inv ( ^ _61) };
     _60 <- ([#"../red_black_tree.rs" 770 35 770 65] Take0.take _61);
@@ -10629,7 +10629,7 @@ module RedBlackTree_Impl15_DeleteRec
       end
   }
   BB48 {
-    _75 <- Borrow.borrow_mut ( * node);
+    _75 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _75) ; };
     assume { Inv5.inv ( ^ _75) };
     _74 <- ([#"../red_black_tree.rs" 774 31 774 52] MoveRedRight0.move_red_right _75);
@@ -10637,7 +10637,7 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB49
   }
   BB49 {
-    _73 <- Borrow.borrow_mut ( * _74);
+    _73 <- Borrow.borrow_final ( * _74) (Borrow.get_id _74);
     _74 <- { _74 with current = ( ^ _73) ; };
     assume { Inv5.inv ( ^ _73) };
     assert { [@expl:type invariant] Inv6.inv node };
@@ -10681,13 +10681,13 @@ module RedBlackTree_Impl15_DeleteRec
     _83 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_key ( * node));
     node <- { node with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * node in RedBlackTree_Node_Type.C_Node a b ( ^ _83) d e) ; };
     assume { Inv9.inv ( ^ _83) };
-    _82 <- Borrow.borrow_mut ( * _83);
+    _82 <- Borrow.borrow_final ( * _83) (Borrow.get_id _83);
     _83 <- { _83 with current = ( ^ _82) ; };
     assume { Inv9.inv ( ^ _82) };
     _85 <- Borrow.borrow_mut (let (a, _) = kv in a);
     kv <- (let (a, b) = kv in ( ^ _85, b));
     assume { Inv9.inv ( ^ _85) };
-    _84 <- Borrow.borrow_mut ( * _85);
+    _84 <- Borrow.borrow_final ( * _85) (Borrow.get_id _85);
     _85 <- { _85 with current = ( ^ _84) ; };
     assume { Inv9.inv ( ^ _84) };
     _81 <- ([#"../red_black_tree.rs" 779 24 779 64] Swap0.swap _82 _84);
@@ -10703,13 +10703,13 @@ module RedBlackTree_Impl15_DeleteRec
     _88 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_val ( * node));
     node <- { node with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * node in RedBlackTree_Node_Type.C_Node a b c ( ^ _88) e) ; };
     assume { Inv11.inv ( ^ _88) };
-    _87 <- Borrow.borrow_mut ( * _88);
+    _87 <- Borrow.borrow_final ( * _88) (Borrow.get_id _88);
     _88 <- { _88 with current = ( ^ _87) ; };
     assume { Inv11.inv ( ^ _87) };
     _90 <- Borrow.borrow_mut (let (_, a) = kv in a);
     kv <- (let (a, b) = kv in (a,  ^ _90));
     assume { Inv11.inv ( ^ _90) };
-    _89 <- Borrow.borrow_mut ( * _90);
+    _89 <- Borrow.borrow_final ( * _90) (Borrow.get_id _90);
     _90 <- { _90 with current = ( ^ _89) ; };
     assume { Inv11.inv ( ^ _89) };
     _86 <- ([#"../red_black_tree.rs" 780 24 780 64] Swap1.swap _87 _89);
@@ -10765,7 +10765,7 @@ module RedBlackTree_Impl15_DeleteRec
     goto BB69
   }
   BB69 {
-    _97 <- Borrow.borrow_mut ( * node);
+    _97 <- Borrow.borrow_final ( * node) (Borrow.get_id node);
     node <- { node with current = ( ^ _97) ; };
     assume { Inv5.inv ( ^ _97) };
     _96 <- ([#"../red_black_tree.rs" 788 8 788 22] Balance0.balance _97);
@@ -11215,7 +11215,7 @@ module RedBlackTree_Impl15_Delete
     goto BB3
   }
   BB3 {
-    node <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _10));
+    node <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _10)) (Borrow.inherit_id (Borrow.get_id _10) 1);
     _10 <- { _10 with current = (let Core_Option_Option_Type.C_Some a =  * _10 in Core_Option_Option_Type.C_Some ( ^ node)) ; };
     assume { Inv1.inv ( ^ node) };
     _14 <- ([#"../red_black_tree.rs" 804 16 804 34] IsRed0.is_red (RedBlackTree_Node_Type.node_left ( * node)));
@@ -11275,7 +11275,7 @@ module RedBlackTree_Impl15_Delete
       end
   }
   BB11 {
-    _27 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * self));
+    _27 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let RedBlackTree_Tree_Type.C_Tree a =  * self in RedBlackTree_Tree_Type.C_Tree ( ^ _27)) ; };
     assume { Inv0.inv ( ^ _27) };
     _26 <- ([#"../red_black_tree.rs" 812 12 812 30] AsMut0.as_mut _27);
@@ -12180,7 +12180,7 @@ module RedBlackTree_Impl15_GetMut
     goto BB4
   }
   BB4 {
-    _23 <- Borrow.borrow_mut (RedBlackTree_Tree_Type.tree_node ( * tree));
+    _23 <- Borrow.borrow_final (RedBlackTree_Tree_Type.tree_node ( * tree)) (Borrow.inherit_id (Borrow.get_id tree) 1);
     tree <- { tree with current = (let RedBlackTree_Tree_Type.C_Tree a =  * tree in RedBlackTree_Tree_Type.C_Tree ( ^ _23)) ; };
     assume { Inv3.inv ( ^ _23) };
     switch ( * _23)
@@ -12192,7 +12192,7 @@ module RedBlackTree_Impl15_GetMut
     goto BB6
   }
   BB6 {
-    node <- Borrow.borrow_mut (Core_Option_Option_Type.some_0 ( * _23));
+    node <- Borrow.borrow_final (Core_Option_Option_Type.some_0 ( * _23)) (Borrow.inherit_id (Borrow.get_id _23) 1);
     _23 <- { _23 with current = (let Core_Option_Option_Type.C_Some a =  * _23 in Core_Option_Option_Type.C_Some ( ^ node)) ; };
     assume { Inv4.inv ( ^ node) };
     _29 <- RedBlackTree_Node_Type.node_key ( * node);
@@ -12218,7 +12218,7 @@ module RedBlackTree_Impl15_GetMut
     _37 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_right ( * node));
     node <- { node with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * node in RedBlackTree_Node_Type.C_Node a b c d ( ^ _37)) ; };
     assume { Inv6.inv ( ^ _37) };
-    _36 <- Borrow.borrow_mut ( * _37);
+    _36 <- Borrow.borrow_final ( * _37) (Borrow.get_id _37);
     _37 <- { _37 with current = ( ^ _36) ; };
     assume { Inv6.inv ( ^ _36) };
     assert { [@expl:type invariant] Inv7.inv tree };
@@ -12245,7 +12245,7 @@ module RedBlackTree_Impl15_GetMut
     _32 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_left ( * node));
     node <- { node with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * node in RedBlackTree_Node_Type.C_Node ( ^ _32) b c d e) ; };
     assume { Inv6.inv ( ^ _32) };
-    _31 <- Borrow.borrow_mut ( * _32);
+    _31 <- Borrow.borrow_final ( * _32) (Borrow.get_id _32);
     _32 <- { _32 with current = ( ^ _31) ; };
     assume { Inv6.inv ( ^ _31) };
     assert { [@expl:type invariant] Inv7.inv tree };
@@ -12263,7 +12263,7 @@ module RedBlackTree_Impl15_GetMut
     _35 <- Borrow.borrow_mut (RedBlackTree_Node_Type.node_val ( * node));
     node <- { node with current = (let RedBlackTree_Node_Type.C_Node a b c d e =  * node in RedBlackTree_Node_Type.C_Node a b c ( ^ _35) e) ; };
     assume { Inv1.inv ( ^ _35) };
-    _34 <- Borrow.borrow_mut ( * _35);
+    _34 <- Borrow.borrow_final ( * _35) (Borrow.get_id _35);
     _35 <- { _35 with current = ( ^ _34) ; };
     assume { Inv1.inv ( ^ _34) };
     _0 <- Core_Option_Option_Type.C_Some _34;
diff --git a/creusot/tests/should_succeed/resolve_uninit.mlcfg b/creusot/tests/should_succeed/resolve_uninit.mlcfg
index 107fa5e7e7..597b664fbf 100644
--- a/creusot/tests/should_succeed/resolve_uninit.mlcfg
+++ b/creusot/tests/should_succeed/resolve_uninit.mlcfg
@@ -219,14 +219,14 @@ module ResolveUninit_InitJoin
   BB1 {
     _8 <- Borrow.borrow_mut x;
     x <-  ^ _8;
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     z <- _7;
     _7 <- any borrowed int32;
     assume { Resolve0.resolve _8 };
-    _10 <- Borrow.borrow_mut ( * z);
+    _10 <- Borrow.borrow_final ( * z) (Borrow.get_id z);
     z <- { z with current = ( ^ _10) ; };
-    _9 <- Borrow.borrow_mut ( * _10);
+    _9 <- Borrow.borrow_final ( * _10) (Borrow.get_id _10);
     _10 <- { _10 with current = ( ^ _9) ; };
     y <- _9;
     _9 <- any borrowed int32;
@@ -237,7 +237,7 @@ module ResolveUninit_InitJoin
   BB2 {
     _12 <- Borrow.borrow_mut x;
     x <-  ^ _12;
-    _11 <- Borrow.borrow_mut ( * _12);
+    _11 <- Borrow.borrow_final ( * _12) (Borrow.get_id _12);
     _12 <- { _12 with current = ( ^ _11) ; };
     y <- _11;
     _11 <- any borrowed int32;
diff --git a/creusot/tests/should_succeed/result/own.mlcfg b/creusot/tests/should_succeed/result/own.mlcfg
index 2c45ee1e4b..d9ca26f93f 100644
--- a/creusot/tests/should_succeed/result/own.mlcfg
+++ b/creusot/tests/should_succeed/result/own.mlcfg
@@ -711,10 +711,10 @@ module Own_Impl0_AsMut
     goto BB4
   }
   BB2 {
-    x1 <- Borrow.borrow_mut (Own_OwnResult_Type.err_0 ( * self));
+    x1 <- Borrow.borrow_final (Own_OwnResult_Type.err_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let Own_OwnResult_Type.C_Err a =  * self in Own_OwnResult_Type.C_Err ( ^ x1)) ; };
     assume { Inv2.inv ( ^ x1) };
-    _7 <- Borrow.borrow_mut ( * x1);
+    _7 <- Borrow.borrow_final ( * x1) (Borrow.get_id x1);
     x1 <- { x1 with current = ( ^ _7) ; };
     assume { Inv2.inv ( ^ _7) };
     _0 <- Own_OwnResult_Type.C_Err _7;
@@ -729,10 +729,10 @@ module Own_Impl0_AsMut
     absurd
   }
   BB4 {
-    x <- Borrow.borrow_mut (Own_OwnResult_Type.ok_0 ( * self));
+    x <- Borrow.borrow_final (Own_OwnResult_Type.ok_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let Own_OwnResult_Type.C_Ok a =  * self in Own_OwnResult_Type.C_Ok ( ^ x)) ; };
     assume { Inv0.inv ( ^ x) };
-    _5 <- Borrow.borrow_mut ( * x);
+    _5 <- Borrow.borrow_final ( * x) (Borrow.get_id x);
     x <- { x with current = ( ^ _5) ; };
     assume { Inv0.inv ( ^ _5) };
     _0 <- Own_OwnResult_Type.C_Ok _5;
diff --git a/creusot/tests/should_succeed/rusthorn/inc_max.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_max.mlcfg
index f2a8fd8bc8..04382e4f6f 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_max.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_max.mlcfg
@@ -64,23 +64,23 @@ module IncMax_TakeMax
   }
   BB1 {
     assume { Resolve0.resolve mb };
-    _9 <- Borrow.borrow_mut ( * ma);
+    _9 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _9) ; };
-    _5 <- Borrow.borrow_mut ( * _9);
+    _5 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _5) ; };
     assume { Resolve0.resolve _9 };
     goto BB3
   }
   BB2 {
     assume { Resolve0.resolve ma };
-    _5 <- Borrow.borrow_mut ( * mb);
+    _5 <- Borrow.borrow_final ( * mb) (Borrow.get_id mb);
     mb <- { mb with current = ( ^ _5) ; };
     goto BB3
   }
   BB3 {
-    _3 <- Borrow.borrow_mut ( * _5);
+    _3 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _3) ; };
-    _0 <- Borrow.borrow_mut ( * _3);
+    _0 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _3 };
@@ -122,11 +122,11 @@ module IncMax_IncMax
   BB0 {
     _6 <- Borrow.borrow_mut a;
     a <-  ^ _6;
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     _8 <- Borrow.borrow_mut b;
     b <-  ^ _8;
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     mc <- ([#"../inc_max.rs" 16 13 16 37] TakeMax0.take_max _5 _7);
     _5 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/rusthorn/inc_max_3.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_max_3.mlcfg
index e5a34e45d8..97daaa96be 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_max_3.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_max_3.mlcfg
@@ -86,11 +86,11 @@ module IncMax3_IncMax3
   BB1 {
     _12 <- Borrow.borrow_mut ma;
     ma <-  ^ _12;
-    _11 <- Borrow.borrow_mut ( * _12);
+    _11 <- Borrow.borrow_final ( * _12) (Borrow.get_id _12);
     _12 <- { _12 with current = ( ^ _11) ; };
     _14 <- Borrow.borrow_mut mb;
     mb <-  ^ _14;
-    _13 <- Borrow.borrow_mut ( * _14);
+    _13 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _13) ; };
     _10 <- ([#"../inc_max_3.rs" 14 8 14 30] Swap0.swap _11 _13);
     _11 <- any borrowed (borrowed uint32);
@@ -116,11 +116,11 @@ module IncMax3_IncMax3
   BB5 {
     _21 <- Borrow.borrow_mut mb;
     mb <-  ^ _21;
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     _23 <- Borrow.borrow_mut mc;
     mc <-  ^ _23;
-    _22 <- Borrow.borrow_mut ( * _23);
+    _22 <- Borrow.borrow_final ( * _23) (Borrow.get_id _23);
     _23 <- { _23 with current = ( ^ _22) ; };
     _19 <- ([#"../inc_max_3.rs" 17 8 17 30] Swap0.swap _20 _22);
     _20 <- any borrowed (borrowed uint32);
@@ -148,11 +148,11 @@ module IncMax3_IncMax3
   BB9 {
     _30 <- Borrow.borrow_mut ma;
     ma <-  ^ _30;
-    _29 <- Borrow.borrow_mut ( * _30);
+    _29 <- Borrow.borrow_final ( * _30) (Borrow.get_id _30);
     _30 <- { _30 with current = ( ^ _29) ; };
     _32 <- Borrow.borrow_mut mb;
     mb <-  ^ _32;
-    _31 <- Borrow.borrow_mut ( * _32);
+    _31 <- Borrow.borrow_final ( * _32) (Borrow.get_id _32);
     _32 <- { _32 with current = ( ^ _31) ; };
     _28 <- ([#"../inc_max_3.rs" 20 8 20 30] Swap0.swap _29 _31);
     _29 <- any borrowed (borrowed uint32);
@@ -216,15 +216,15 @@ module IncMax3_TestIncMax3
   BB0 {
     _7 <- Borrow.borrow_mut a;
     a <-  ^ _7;
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     _9 <- Borrow.borrow_mut b;
     b <-  ^ _9;
-    _8 <- Borrow.borrow_mut ( * _9);
+    _8 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _8) ; };
     _11 <- Borrow.borrow_mut c;
     c <-  ^ _11;
-    _10 <- Borrow.borrow_mut ( * _11);
+    _10 <- Borrow.borrow_final ( * _11) (Borrow.get_id _11);
     _11 <- { _11 with current = ( ^ _10) ; };
     _5 <- ([#"../inc_max_3.rs" 28 4 28 37] IncMax30.inc_max_3 _6 _8 _10);
     _6 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/rusthorn/inc_max_many.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_max_many.mlcfg
index 464fef4ba7..1f8b4b7340 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_max_many.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_max_many.mlcfg
@@ -64,23 +64,23 @@ module IncMaxMany_TakeMax
   }
   BB1 {
     assume { Resolve0.resolve mb };
-    _9 <- Borrow.borrow_mut ( * ma);
+    _9 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _9) ; };
-    _5 <- Borrow.borrow_mut ( * _9);
+    _5 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _5) ; };
     assume { Resolve0.resolve _9 };
     goto BB3
   }
   BB2 {
     assume { Resolve0.resolve ma };
-    _5 <- Borrow.borrow_mut ( * mb);
+    _5 <- Borrow.borrow_final ( * mb) (Borrow.get_id mb);
     mb <- { mb with current = ( ^ _5) ; };
     goto BB3
   }
   BB3 {
-    _3 <- Borrow.borrow_mut ( * _5);
+    _3 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _3) ; };
-    _0 <- Borrow.borrow_mut ( * _3);
+    _0 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _3 };
@@ -124,11 +124,11 @@ module IncMaxMany_IncMaxMany
   BB0 {
     _7 <- Borrow.borrow_mut a;
     a <-  ^ _7;
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     _9 <- Borrow.borrow_mut b;
     b <-  ^ _9;
-    _8 <- Borrow.borrow_mut ( * _9);
+    _8 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _8) ; };
     mc <- ([#"../inc_max_many.rs" 16 13 16 37] TakeMax0.take_max _6 _8);
     _6 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/rusthorn/inc_max_repeat.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_max_repeat.mlcfg
index 393ef71123..d62e7fd9fc 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_max_repeat.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_max_repeat.mlcfg
@@ -64,23 +64,23 @@ module IncMaxRepeat_TakeMax
   }
   BB1 {
     assume { Resolve0.resolve mb };
-    _9 <- Borrow.borrow_mut ( * ma);
+    _9 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _9) ; };
-    _5 <- Borrow.borrow_mut ( * _9);
+    _5 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _5) ; };
     assume { Resolve0.resolve _9 };
     goto BB3
   }
   BB2 {
     assume { Resolve0.resolve ma };
-    _5 <- Borrow.borrow_mut ( * mb);
+    _5 <- Borrow.borrow_final ( * mb) (Borrow.get_id mb);
     mb <- { mb with current = ( ^ _5) ; };
     goto BB3
   }
   BB3 {
-    _3 <- Borrow.borrow_mut ( * _5);
+    _3 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _3) ; };
-    _0 <- Borrow.borrow_mut ( * _3);
+    _0 <- Borrow.borrow_final ( * _3) (Borrow.get_id _3);
     _3 <- { _3 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _3 };
@@ -673,7 +673,7 @@ module IncMaxRepeat_IncMaxRepeat
   BB5 {
     _20 <- Borrow.borrow_mut iter;
     iter <-  ^ _20;
-    _19 <- Borrow.borrow_mut ( * _20);
+    _19 <- Borrow.borrow_final ( * _20) (Borrow.get_id _20);
     _20 <- { _20 with current = ( ^ _19) ; };
     _18 <- ([#"../inc_max_repeat.rs" 16 4 16 86] Next0.next _19);
     _19 <- any borrowed (Core_Ops_Range_Range_Type.t_range uint32);
@@ -708,11 +708,11 @@ module IncMaxRepeat_IncMaxRepeat
     _23 <- any Ghost.ghost_ty (Seq.seq uint32);
     _27 <- Borrow.borrow_mut a;
     a <-  ^ _27;
-    _26 <- Borrow.borrow_mut ( * _27);
+    _26 <- Borrow.borrow_final ( * _27) (Borrow.get_id _27);
     _27 <- { _27 with current = ( ^ _26) ; };
     _29 <- Borrow.borrow_mut b;
     b <-  ^ _29;
-    _28 <- Borrow.borrow_mut ( * _29);
+    _28 <- Borrow.borrow_final ( * _29) (Borrow.get_id _29);
     _29 <- { _29 with current = ( ^ _28) ; };
     mc <- ([#"../inc_max_repeat.rs" 19 17 19 41] TakeMax0.take_max _26 _28);
     _26 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/rusthorn/inc_some_2_list.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_some_2_list.mlcfg
index 394905900e..3f9c40afdf 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_some_2_list.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_some_2_list.mlcfg
@@ -336,9 +336,9 @@ module IncSome2List_Impl0_TakeSomeRest
     absurd
   }
   BB4 {
-    ma <- Borrow.borrow_mut (IncSome2List_List_Type.cons_0 ( * self));
+    ma <- Borrow.borrow_final (IncSome2List_List_Type.cons_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let IncSome2List_List_Type.C_Cons a b =  * self in IncSome2List_List_Type.C_Cons ( ^ ma) b) ; };
-    ml <- Borrow.borrow_mut (IncSome2List_List_Type.cons_1 ( * self));
+    ml <- Borrow.borrow_final (IncSome2List_List_Type.cons_1 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let IncSome2List_List_Type.C_Cons a b =  * self in IncSome2List_List_Type.C_Cons a ( ^ ml)) ; };
     _8 <- ([#"../inc_some_2_list.rs" 57 16 57 45] Ghost.new (LemmaSumNonneg0.lemma_sum_nonneg ( * ml)));
     goto BB5
@@ -354,7 +354,7 @@ module IncSome2List_Impl0_TakeSomeRest
       end
   }
   BB7 {
-    _11 <- Borrow.borrow_mut ( * ma);
+    _11 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _11) ; };
     _12 <- Borrow.borrow_mut ( * ml);
     ml <- { ml with current = ( ^ _12) ; };
@@ -507,7 +507,7 @@ module IncSome2List_IncSome2List
     ml <- (let (_, a) = _9 in a);
     _9 <- (let (a, b) = _9 in (a, any borrowed (IncSome2List_List_Type.t_list)));
     assume { Resolve0.resolve _9 };
-    _13 <- Borrow.borrow_mut ( * ml);
+    _13 <- Borrow.borrow_final ( * ml) (Borrow.get_id ml);
     ml <- { ml with current = ( ^ _13) ; };
     _12 <- ([#"../inc_some_2_list.rs" 73 18 73 37] TakeSomeRest0.take_some_rest _13);
     _13 <- any borrowed (IncSome2List_List_Type.t_list);
diff --git a/creusot/tests/should_succeed/rusthorn/inc_some_2_tree.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_some_2_tree.mlcfg
index 96cbe1e7e6..1ef32ac51a 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_some_2_tree.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_some_2_tree.mlcfg
@@ -357,11 +357,11 @@ module IncSome2Tree_Impl0_TakeSomeRest
     absurd
   }
   BB4 {
-    mtl <- Borrow.borrow_mut (IncSome2Tree_Tree_Type.node_0 ( * self));
+    mtl <- Borrow.borrow_final (IncSome2Tree_Tree_Type.node_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let IncSome2Tree_Tree_Type.C_Node a b c =  * self in IncSome2Tree_Tree_Type.C_Node ( ^ mtl) b c) ; };
-    ma <- Borrow.borrow_mut (IncSome2Tree_Tree_Type.node_1 ( * self));
+    ma <- Borrow.borrow_final (IncSome2Tree_Tree_Type.node_1 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let IncSome2Tree_Tree_Type.C_Node a b c =  * self in IncSome2Tree_Tree_Type.C_Node a ( ^ ma) c) ; };
-    mtr <- Borrow.borrow_mut (IncSome2Tree_Tree_Type.node_2 ( * self));
+    mtr <- Borrow.borrow_final (IncSome2Tree_Tree_Type.node_2 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 3);
     self <- { self with current = (let IncSome2Tree_Tree_Type.C_Node a b c =  * self in IncSome2Tree_Tree_Type.C_Node a b ( ^ mtr)) ; };
     assert { [@expl:assertion] [#"../inc_some_2_tree.rs" 67 20 67 42] let _ = LemmaSumNonneg0.lemma_sum_nonneg ( * mtl) in let _ = LemmaSumNonneg0.lemma_sum_nonneg ( * mtr) in true };
     _11 <- ([#"../inc_some_2_tree.rs" 71 19 71 27] Random0.random ());
@@ -374,7 +374,7 @@ module IncSome2Tree_Impl0_TakeSomeRest
       end
   }
   BB6 {
-    _12 <- Borrow.borrow_mut ( * ma);
+    _12 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _12) ; };
     _15 <- ([#"../inc_some_2_tree.rs" 72 28 72 36] Random0.random ());
     goto BB7
@@ -389,7 +389,7 @@ module IncSome2Tree_Impl0_TakeSomeRest
     assume { Resolve1.resolve mtr };
     _16 <- Borrow.borrow_mut ( * mtl);
     mtl <- { mtl with current = ( ^ _16) ; };
-    _14 <- Borrow.borrow_mut ( * _16);
+    _14 <- Borrow.borrow_final ( * _16) (Borrow.get_id _16);
     _16 <- { _16 with current = ( ^ _14) ; };
     assume { Resolve2.resolve _16 };
     goto BB10
@@ -401,7 +401,7 @@ module IncSome2Tree_Impl0_TakeSomeRest
     goto BB10
   }
   BB10 {
-    _13 <- Borrow.borrow_mut ( * _14);
+    _13 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _13) ; };
     _0 <- (_12, _13);
     _12 <- any borrowed uint32;
@@ -579,7 +579,7 @@ module IncSome2Tree_IncSome2Tree
     mt <- (let (_, a) = _9 in a);
     _9 <- (let (a, b) = _9 in (a, any borrowed (IncSome2Tree_Tree_Type.t_tree)));
     assume { Resolve0.resolve _9 };
-    _13 <- Borrow.borrow_mut ( * mt);
+    _13 <- Borrow.borrow_final ( * mt) (Borrow.get_id mt);
     mt <- { mt with current = ( ^ _13) ; };
     _12 <- ([#"../inc_some_2_tree.rs" 88 18 88 37] TakeSomeRest0.take_some_rest _13);
     _13 <- any borrowed (IncSome2Tree_Tree_Type.t_tree);
diff --git a/creusot/tests/should_succeed/rusthorn/inc_some_list.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_some_list.mlcfg
index 28fcde9e57..025ff9e209 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_some_list.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_some_list.mlcfg
@@ -338,9 +338,9 @@ module IncSomeList_Impl0_TakeSome
     absurd
   }
   BB4 {
-    ma <- Borrow.borrow_mut (IncSomeList_List_Type.cons_0 ( * self));
+    ma <- Borrow.borrow_final (IncSomeList_List_Type.cons_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let IncSomeList_List_Type.C_Cons a b =  * self in IncSomeList_List_Type.C_Cons ( ^ ma) b) ; };
-    ml <- Borrow.borrow_mut (IncSomeList_List_Type.cons_1 ( * self));
+    ml <- Borrow.borrow_final (IncSomeList_List_Type.cons_1 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let IncSomeList_List_Type.C_Cons a b =  * self in IncSomeList_List_Type.C_Cons a ( ^ ml)) ; };
     _10 <- ([#"../inc_some_list.rs" 54 16 54 45] Ghost.new (LemmaSumNonneg0.lemma_sum_nonneg ( * ml)));
     goto BB5
@@ -357,9 +357,9 @@ module IncSomeList_Impl0_TakeSome
   }
   BB7 {
     assume { Resolve1.resolve ml };
-    _14 <- Borrow.borrow_mut ( * ma);
+    _14 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _14) ; };
-    _12 <- Borrow.borrow_mut ( * _14);
+    _12 <- Borrow.borrow_final ( * _14) (Borrow.get_id _14);
     _14 <- { _14 with current = ( ^ _12) ; };
     assume { Resolve0.resolve _14 };
     goto BB10
@@ -373,23 +373,23 @@ module IncSomeList_Impl0_TakeSome
     goto BB9
   }
   BB9 {
-    _12 <- Borrow.borrow_mut ( * _15);
+    _12 <- Borrow.borrow_final ( * _15) (Borrow.get_id _15);
     _15 <- { _15 with current = ( ^ _12) ; };
     assume { Resolve0.resolve _15 };
     goto BB10
   }
   BB10 {
-    _9 <- Borrow.borrow_mut ( * _12);
+    _9 <- Borrow.borrow_final ( * _12) (Borrow.get_id _12);
     _12 <- { _12 with current = ( ^ _9) ; };
-    _5 <- Borrow.borrow_mut ( * _9);
+    _5 <- Borrow.borrow_final ( * _9) (Borrow.get_id _9);
     _9 <- { _9 with current = ( ^ _5) ; };
     assume { Resolve0.resolve _12 };
     assume { Resolve0.resolve _9 };
     assume { Resolve1.resolve ml };
     assume { Resolve0.resolve ma };
-    _2 <- Borrow.borrow_mut ( * _5);
+    _2 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _2) ; };
-    _0 <- Borrow.borrow_mut ( * _2);
+    _0 <- Borrow.borrow_final ( * _2) (Borrow.get_id _2);
     _2 <- { _2 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _2 };
diff --git a/creusot/tests/should_succeed/rusthorn/inc_some_tree.mlcfg b/creusot/tests/should_succeed/rusthorn/inc_some_tree.mlcfg
index 14c815ed4d..29f44c4185 100644
--- a/creusot/tests/should_succeed/rusthorn/inc_some_tree.mlcfg
+++ b/creusot/tests/should_succeed/rusthorn/inc_some_tree.mlcfg
@@ -358,11 +358,11 @@ module IncSomeTree_Impl0_TakeSome
     absurd
   }
   BB4 {
-    mtl <- Borrow.borrow_mut (IncSomeTree_Tree_Type.node_0 ( * self));
+    mtl <- Borrow.borrow_final (IncSomeTree_Tree_Type.node_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let IncSomeTree_Tree_Type.C_Node a b c =  * self in IncSomeTree_Tree_Type.C_Node ( ^ mtl) b c) ; };
-    ma <- Borrow.borrow_mut (IncSomeTree_Tree_Type.node_1 ( * self));
+    ma <- Borrow.borrow_final (IncSomeTree_Tree_Type.node_1 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let IncSomeTree_Tree_Type.C_Node a b c =  * self in IncSomeTree_Tree_Type.C_Node a ( ^ ma) c) ; };
-    mtr <- Borrow.borrow_mut (IncSomeTree_Tree_Type.node_2 ( * self));
+    mtr <- Borrow.borrow_final (IncSomeTree_Tree_Type.node_2 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 3);
     self <- { self with current = (let IncSomeTree_Tree_Type.C_Node a b c =  * self in IncSomeTree_Tree_Type.C_Node a b ( ^ mtr)) ; };
     assert { [@expl:assertion] [#"../inc_some_tree.rs" 65 20 65 42] let _ = LemmaSumNonneg0.lemma_sum_nonneg ( * mtl) in let _ = LemmaSumNonneg0.lemma_sum_nonneg ( * mtr) in true };
     _14 <- ([#"../inc_some_tree.rs" 69 19 69 27] Random0.random ());
@@ -377,9 +377,9 @@ module IncSomeTree_Impl0_TakeSome
   BB6 {
     assume { Resolve1.resolve mtr };
     assume { Resolve1.resolve mtl };
-    _15 <- Borrow.borrow_mut ( * ma);
+    _15 <- Borrow.borrow_final ( * ma) (Borrow.get_id ma);
     ma <- { ma with current = ( ^ _15) ; };
-    _13 <- Borrow.borrow_mut ( * _15);
+    _13 <- Borrow.borrow_final ( * _15) (Borrow.get_id _15);
     _15 <- { _15 with current = ( ^ _13) ; };
     assume { Resolve0.resolve _15 };
     goto BB14
@@ -404,9 +404,9 @@ module IncSomeTree_Impl0_TakeSome
     goto BB10
   }
   BB10 {
-    _17 <- Borrow.borrow_mut ( * _18);
+    _17 <- Borrow.borrow_final ( * _18) (Borrow.get_id _18);
     _18 <- { _18 with current = ( ^ _17) ; };
-    _13 <- Borrow.borrow_mut ( * _17);
+    _13 <- Borrow.borrow_final ( * _17) (Borrow.get_id _17);
     _17 <- { _17 with current = ( ^ _13) ; };
     assume { Resolve0.resolve _18 };
     assume { Resolve0.resolve _17 };
@@ -421,7 +421,7 @@ module IncSomeTree_Impl0_TakeSome
     goto BB12
   }
   BB12 {
-    _13 <- Borrow.borrow_mut ( * _20);
+    _13 <- Borrow.borrow_final ( * _20) (Borrow.get_id _20);
     _20 <- { _20 with current = ( ^ _13) ; };
     assume { Resolve0.resolve _20 };
     goto BB13
@@ -430,18 +430,18 @@ module IncSomeTree_Impl0_TakeSome
     goto BB14
   }
   BB14 {
-    _10 <- Borrow.borrow_mut ( * _13);
+    _10 <- Borrow.borrow_final ( * _13) (Borrow.get_id _13);
     _13 <- { _13 with current = ( ^ _10) ; };
-    _5 <- Borrow.borrow_mut ( * _10);
+    _5 <- Borrow.borrow_final ( * _10) (Borrow.get_id _10);
     _10 <- { _10 with current = ( ^ _5) ; };
     assume { Resolve0.resolve _13 };
     assume { Resolve0.resolve _10 };
     assume { Resolve1.resolve mtr };
     assume { Resolve0.resolve ma };
     assume { Resolve1.resolve mtl };
-    _2 <- Borrow.borrow_mut ( * _5);
+    _2 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _2) ; };
-    _0 <- Borrow.borrow_mut ( * _2);
+    _0 <- Borrow.borrow_final ( * _2) (Borrow.get_id _2);
     _2 <- { _2 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _2 };
diff --git a/creusot/tests/should_succeed/selection_sort_generic.mlcfg b/creusot/tests/should_succeed/selection_sort_generic.mlcfg
index d0effa110e..b964e3ccdf 100644
--- a/creusot/tests/should_succeed/selection_sort_generic.mlcfg
+++ b/creusot/tests/should_succeed/selection_sort_generic.mlcfg
@@ -2363,7 +2363,7 @@ module SelectionSortGeneric_SelectionSort
   BB7 {
     _22 <- Borrow.borrow_mut iter;
     iter <-  ^ _22;
-    _21 <- Borrow.borrow_mut ( * _22);
+    _21 <- Borrow.borrow_final ( * _22) (Borrow.get_id _22);
     _22 <- { _22 with current = ( ^ _21) ; };
     _20 <- ([#"../selection_sort_generic.rs" 35 4 35 43] Next0.next _21);
     _21 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
@@ -2427,7 +2427,7 @@ module SelectionSortGeneric_SelectionSort
   BB19 {
     _46 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _46;
-    _45 <- Borrow.borrow_mut ( * _46);
+    _45 <- Borrow.borrow_final ( * _46) (Borrow.get_id _46);
     _46 <- { _46 with current = ( ^ _45) ; };
     _44 <- ([#"../selection_sort_generic.rs" 41 8 41 121] Next0.next _45);
     _45 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/sparse_array.mlcfg b/creusot/tests/should_succeed/sparse_array.mlcfg
index f6d69ba210..3904d218c6 100644
--- a/creusot/tests/should_succeed/sparse_array.mlcfg
+++ b/creusot/tests/should_succeed/sparse_array.mlcfg
@@ -1523,7 +1523,7 @@ module SparseArray_Impl2_Set
     goto BB1
   }
   BB1 {
-    _10 <- Borrow.borrow_mut (SparseArray_Sparse_Type.sparse_values ( * self));
+    _10 <- Borrow.borrow_final (SparseArray_Sparse_Type.sparse_values ( * self)) (Borrow.inherit_id (Borrow.get_id self) 3);
     self <- { self with current = (let SparseArray_Sparse_Type.C_Sparse a b c d e =  * self in SparseArray_Sparse_Type.C_Sparse a b ( ^ _10) d e) ; };
     assume { Inv0.inv ( ^ _10) };
     _9 <- ([#"../sparse_array.rs" 113 8 113 22] IndexMut0.index_mut _10 i);
@@ -1578,7 +1578,7 @@ module SparseArray_Impl2_Set
   BB12 {
     assume { Resolve3.resolve _27 };
     assert { [@expl:assertion] [#"../sparse_array.rs" 118 26 118 46] UIntSize.to_int (SparseArray_Sparse_Type.sparse_n ( * self)) < UIntSize.to_int (SparseArray_Sparse_Type.sparse_size ( * self)) };
-    _33 <- Borrow.borrow_mut (SparseArray_Sparse_Type.sparse_idx ( * self));
+    _33 <- Borrow.borrow_final (SparseArray_Sparse_Type.sparse_idx ( * self)) (Borrow.inherit_id (Borrow.get_id self) 4);
     self <- { self with current = (let SparseArray_Sparse_Type.C_Sparse a b c d e =  * self in SparseArray_Sparse_Type.C_Sparse a b c ( ^ _33) e) ; };
     _32 <- ([#"../sparse_array.rs" 120 12 120 23] IndexMut1.index_mut _33 i);
     _33 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
@@ -1587,7 +1587,7 @@ module SparseArray_Impl2_Set
   BB13 {
     _32 <- { _32 with current = SparseArray_Sparse_Type.sparse_n ( * self) ; };
     assume { Resolve4.resolve _32 };
-    _37 <- Borrow.borrow_mut (SparseArray_Sparse_Type.sparse_back ( * self));
+    _37 <- Borrow.borrow_final (SparseArray_Sparse_Type.sparse_back ( * self)) (Borrow.inherit_id (Borrow.get_id self) 5);
     self <- { self with current = (let SparseArray_Sparse_Type.C_Sparse a b c d e =  * self in SparseArray_Sparse_Type.C_Sparse a b c d ( ^ _37)) ; };
     _36 <- ([#"../sparse_array.rs" 121 12 121 29] IndexMut1.index_mut _37 (SparseArray_Sparse_Type.sparse_n ( * self)));
     _37 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
diff --git a/creusot/tests/should_succeed/split_borrow.mlcfg b/creusot/tests/should_succeed/split_borrow.mlcfg
index 3b3345ab96..f571ed7c00 100644
--- a/creusot/tests/should_succeed/split_borrow.mlcfg
+++ b/creusot/tests/should_succeed/split_borrow.mlcfg
@@ -198,7 +198,7 @@ module SplitBorrow_G
     a <- (SplitBorrow_MyInt_Type.C_MyInt ([#"../split_borrow.rs" 24 23 24 24] (1 : usize)), SplitBorrow_MyInt_Type.C_MyInt ([#"../split_borrow.rs" 24 33 24 34] (2 : usize)));
     x <- Borrow.borrow_mut a;
     a <-  ^ x;
-    _z <- Borrow.borrow_mut (let (_, a) =  * x in a);
+    _z <- Borrow.borrow_final (let (_, a) =  * x in a) (Borrow.inherit_id (Borrow.get_id x) 2);
     x <- { x with current = (let (a, b) =  * x in (a,  ^ _z)) ; };
     assume { Resolve0.resolve _z };
     x <- { x with current = (let (a, b) =  * x in (SplitBorrow_MyInt_Type.C_MyInt ([#"../split_borrow.rs" 29 19 29 20] (3 : usize)), b)) ; };
diff --git a/creusot/tests/should_succeed/sum.mlcfg b/creusot/tests/should_succeed/sum.mlcfg
index 8443456311..3e520927f1 100644
--- a/creusot/tests/should_succeed/sum.mlcfg
+++ b/creusot/tests/should_succeed/sum.mlcfg
@@ -1176,7 +1176,7 @@ module Sum_SumFirstN
   BB6 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../sum.rs" 8 4 8 67] Next0.next _18);
     _18 <- any borrowed (Core_Ops_Range_RangeInclusive_Type.t_rangeinclusive uint32);
diff --git a/creusot/tests/should_succeed/sum_of_odds.mlcfg b/creusot/tests/should_succeed/sum_of_odds.mlcfg
index 5b733cf251..b481ff030b 100644
--- a/creusot/tests/should_succeed/sum_of_odds.mlcfg
+++ b/creusot/tests/should_succeed/sum_of_odds.mlcfg
@@ -727,7 +727,7 @@ module SumOfOdds_ComputeSumOfOdd
   BB5 {
     _20 <- Borrow.borrow_mut iter;
     iter <-  ^ _20;
-    _19 <- Borrow.borrow_mut ( * _20);
+    _19 <- Borrow.borrow_final ( * _20) (Borrow.get_id _20);
     _20 <- { _20 with current = ( ^ _19) ; };
     _18 <- ([#"../sum_of_odds.rs" 38 4 38 50] Next0.next _19);
     _19 <- any borrowed (Core_Ops_Range_Range_Type.t_range uint32);
diff --git a/creusot/tests/should_succeed/swap_borrows.mlcfg b/creusot/tests/should_succeed/swap_borrows.mlcfg
index e24f195e6e..19d1300eb4 100644
--- a/creusot/tests/should_succeed/swap_borrows.mlcfg
+++ b/creusot/tests/should_succeed/swap_borrows.mlcfg
@@ -219,7 +219,7 @@ module SwapBorrows_F
     a <-  ^ _6;
     _8 <- Borrow.borrow_mut b;
     b <-  ^ _8;
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     p <- ([#"../swap_borrows.rs" 12 12 12 34] Swap0.swap (_6, _7));
     _6 <- any borrowed uint32;
diff --git a/creusot/tests/should_succeed/syntax/05_pearlite.mlcfg b/creusot/tests/should_succeed/syntax/05_pearlite.mlcfg
index 05600f50ba..c5cc3d976b 100644
--- a/creusot/tests/should_succeed/syntax/05_pearlite.mlcfg
+++ b/creusot/tests/should_succeed/syntax/05_pearlite.mlcfg
@@ -457,7 +457,7 @@ module C05Pearlite_Proj
   clone C05Pearlite_Impl0_X_Stub as X0
   function proj [#"../05_pearlite.rs" 72 0 72 35] (x : borrowed (C05Pearlite_S_Type.t_s, C05Pearlite_S_Type.t_s)) : bool
    =
-    [#"../05_pearlite.rs" 71 0 71 8] X0.x {current = let (a, _) =  * x in a; final = let (a, _) =  ^ x in a; addr = Borrow.make_new_addr ()}
+    [#"../05_pearlite.rs" 71 0 71 8] X0.x {current = let (a, _) =  * x in a; final = let (a, _) =  ^ x in a; id = Borrow.inherit_id (Borrow.get_id x) 1}
   val proj [#"../05_pearlite.rs" 72 0 72 35] (x : borrowed (C05Pearlite_S_Type.t_s, C05Pearlite_S_Type.t_s)) : bool
     ensures { result = proj x }
     
@@ -484,7 +484,7 @@ module C05Pearlite_Proj2
   function proj2 [#"../05_pearlite.rs" 78 0 78 41] (x : borrowed (borrowed (C05Pearlite_S_Type.t_s, C05Pearlite_S_Type.t_s))) : bool
     
    =
-    [#"../05_pearlite.rs" 77 0 77 8] X0.x {current = let (a, _) =  *  * x in a; final = let (a, _) =  ^  * x in a; addr = Borrow.make_new_addr ()}
+    [#"../05_pearlite.rs" 77 0 77 8] X0.x {current = let (a, _) =  *  * x in a; final = let (a, _) =  ^  * x in a; id = Borrow.inherit_id (Borrow.get_id ( * x)) 1}
   val proj2 [#"../05_pearlite.rs" 78 0 78 41] (x : borrowed (borrowed (C05Pearlite_S_Type.t_s, C05Pearlite_S_Type.t_s))) : bool
     ensures { result = proj2 x }
     
diff --git a/creusot/tests/should_succeed/take_first_mut.mlcfg b/creusot/tests/should_succeed/take_first_mut.mlcfg
index 25df706d2e..4d96a3def3 100644
--- a/creusot/tests/should_succeed/take_first_mut.mlcfg
+++ b/creusot/tests/should_succeed/take_first_mut.mlcfg
@@ -409,7 +409,7 @@ module TakeFirstMut_TakeFirstMut_Interface
     requires {[#"../take_first_mut.rs" 14 29 14 34] Inv0.inv self_}
     ensures { [#"../take_first_mut.rs" 6 10 13 1] match (result) with
       | Core_Option_Option_Type.C_Some r ->  * r = IndexLogic0.index_logic ( *  * self_) 0 /\  ^ r = IndexLogic0.index_logic ( ^  * self_) 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) > 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self_)) > 0 /\ ShallowModel0.shallow_model ( *  ^ self_) = Tail0.tail (ShallowModel0.shallow_model ( *  * self_)) /\ ShallowModel0.shallow_model ( ^  ^ self_) = Tail0.tail (ShallowModel0.shallow_model ( ^  * self_))
-      | Core_Option_Option_Type.C_None ->  ^ self_ =  * self_ /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) = 0
+      | Core_Option_Option_Type.C_None -> Seq.length (ShallowModel0.shallow_model ( *  ^ self_)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self_)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) = 0
       end }
     ensures { [#"../take_first_mut.rs" 14 57 14 74] Inv1.inv result }
     
@@ -524,7 +524,7 @@ module TakeFirstMut_TakeFirstMut
     requires {[#"../take_first_mut.rs" 14 29 14 34] Inv3.inv self_}
     ensures { [#"../take_first_mut.rs" 6 10 13 1] match (result) with
       | Core_Option_Option_Type.C_Some r ->  * r = IndexLogic0.index_logic ( *  * self_) 0 /\  ^ r = IndexLogic0.index_logic ( ^  * self_) 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) > 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self_)) > 0 /\ ShallowModel0.shallow_model ( *  ^ self_) = Tail0.tail (ShallowModel0.shallow_model ( *  * self_)) /\ ShallowModel0.shallow_model ( ^  ^ self_) = Tail0.tail (ShallowModel0.shallow_model ( ^  * self_))
-      | Core_Option_Option_Type.C_None ->  ^ self_ =  * self_ /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) = 0
+      | Core_Option_Option_Type.C_None -> Seq.length (ShallowModel0.shallow_model ( *  ^ self_)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( ^  * self_)) = 0 /\ Seq.length (ShallowModel0.shallow_model ( *  * self_)) = 0
       end }
     ensures { [#"../take_first_mut.rs" 14 57 14 74] Inv6.inv result }
     
@@ -543,7 +543,7 @@ module TakeFirstMut_TakeFirstMut
     goto BB0
   }
   BB0 {
-    _6 <- Borrow.borrow_mut ( * self_);
+    _6 <- Borrow.borrow_final ( * self_) (Borrow.get_id self_);
     self_ <- { self_ with current = ( ^ _6) ; };
     assume { Inv0.inv ( ^ _6) };
     _5 <- ([#"../take_first_mut.rs" 15 10 15 26] Take0.take _6);
@@ -551,7 +551,7 @@ module TakeFirstMut_TakeFirstMut
     goto BB1
   }
   BB1 {
-    _4 <- Borrow.borrow_mut ( * _5);
+    _4 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _4) ; };
     assume { Inv1.inv ( ^ _4) };
     _3 <- ([#"../take_first_mut.rs" 15 10 15 44] SplitFirstMut0.split_first_mut _4);
@@ -574,7 +574,7 @@ module TakeFirstMut_TakeFirstMut
     _3 <- (let Core_Option_Option_Type.C_Some a = _3 in Core_Option_Option_Type.C_Some (let (a, b) = Core_Option_Option_Type.some_0 _3 in (a, any borrowed (slice t))));
     assert { [@expl:type invariant] Inv2.inv _3 };
     assume { Resolve0.resolve _3 };
-    _11 <- Borrow.borrow_mut ( * rem);
+    _11 <- Borrow.borrow_final ( * rem) (Borrow.get_id rem);
     rem <- { rem with current = ( ^ _11) ; };
     assume { Inv1.inv ( ^ _11) };
     self_ <- { self_ with current = _11 ; };
@@ -583,7 +583,7 @@ module TakeFirstMut_TakeFirstMut
     assume { Resolve2.resolve ( * self_) };
     assert { [@expl:type invariant] Inv3.inv self_ };
     assume { Resolve1.resolve self_ };
-    _12 <- Borrow.borrow_mut ( * first);
+    _12 <- Borrow.borrow_final ( * first) (Borrow.get_id first);
     first <- { first with current = ( ^ _12) ; };
     assume { Inv4.inv ( ^ _12) };
     _0 <- Core_Option_Option_Type.C_Some _12;
diff --git a/creusot/tests/should_succeed/take_first_mut.rs b/creusot/tests/should_succeed/take_first_mut.rs
index 70b9f6a477..b277811053 100644
--- a/creusot/tests/should_succeed/take_first_mut.rs
+++ b/creusot/tests/should_succeed/take_first_mut.rs
@@ -9,7 +9,7 @@ use std::mem;
         (**self_)@.len() > 0 && (^*self_)@.len() > 0 &&
         (*^self_)@ == (**self_)@.tail() && (^^self_)@ == (^*self_)@.tail()
     }
-    None => ^self_ == * self_ && (**self_)@.len() == 0
+    None => (*^self_)@.len() == 0 && (^*self_)@.len() == 0 && (**self_)@.len() == 0
 })]
 pub fn take_first_mut<'a, T>(self_: &mut &'a mut [T]) -> Option<&'a mut T> {
     match mem::take(self_).split_first_mut() {
diff --git a/creusot/tests/should_succeed/type_invariants/borrows.mlcfg b/creusot/tests/should_succeed/type_invariants/borrows.mlcfg
index c5052b9d46..b456ded4ba 100644
--- a/creusot/tests/should_succeed/type_invariants/borrows.mlcfg
+++ b/creusot/tests/should_succeed/type_invariants/borrows.mlcfg
@@ -177,11 +177,11 @@ module Borrows_Impl1_InnerMut
     goto BB0
   }
   BB0 {
-    _5 <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * self));
+    _5 <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let Borrows_NonZero_Type.C_NonZero a =  * self in Borrows_NonZero_Type.C_NonZero ( ^ _5)) ; };
-    _2 <- Borrow.borrow_mut ( * _5);
+    _2 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _2) ; };
-    _0 <- Borrow.borrow_mut ( * _2);
+    _0 <- Borrow.borrow_final ( * _2) (Borrow.get_id _2);
     _2 <- { _2 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _5 };
     assume { Resolve0.resolve _2 };
@@ -390,9 +390,9 @@ module Borrows_Simple
     goto BB0
   }
   BB0 {
-    _6 <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * x));
+    _6 <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * x)) (Borrow.inherit_id (Borrow.get_id x) 1);
     x <- { x with current = (let Borrows_NonZero_Type.C_NonZero a =  * x in Borrows_NonZero_Type.C_NonZero ( ^ _6)) ; };
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     _4 <- ([#"../borrows.rs" 32 4 32 17] Inc0.inc _5);
     _5 <- any borrowed int32;
@@ -472,7 +472,7 @@ module Borrows_Hard
     goto BB0
   }
   BB0 {
-    _7 <- Borrow.borrow_mut ( * x);
+    _7 <- Borrow.borrow_final ( * x) (Borrow.get_id x);
     x <- { x with current = ( ^ _7) ; };
     assume { Inv0.inv ( ^ _7) };
     _6 <- ([#"../borrows.rs" 39 8 39 21] InnerMut0.inner_mut _7);
@@ -480,7 +480,7 @@ module Borrows_Hard
     goto BB1
   }
   BB1 {
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     _4 <- ([#"../borrows.rs" 39 4 39 22] Inc0.inc _5);
     _5 <- any borrowed int32;
@@ -648,9 +648,9 @@ module Borrows_Tuple
   }
   BB0 {
     x <- (let (a, b) = x in (let Borrows_NonZero_Type.C_NonZero a = let (a, _) = x in a in Borrows_NonZero_Type.C_NonZero ([#"../borrows.rs" 46 13 46 14] (0 : int32)), b));
-    _6 <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * (let (_, a) = x in a)));
+    _6 <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * (let (_, a) = x in a))) (Borrow.inherit_id (Borrow.get_id (let (_, a) = x in a)) 1);
     x <- (let (a, b) = x in (a, { (let (_, a) = x in a) with current = (let Borrows_NonZero_Type.C_NonZero a =  * (let (_, a) = x in a) in Borrows_NonZero_Type.C_NonZero ( ^ _6)) ; }));
-    _5 <- Borrow.borrow_mut ( * _6);
+    _5 <- Borrow.borrow_final ( * _6) (Borrow.get_id _6);
     _6 <- { _6 with current = ( ^ _5) ; };
     _4 <- ([#"../borrows.rs" 47 4 47 20] Inc0.inc _5);
     _5 <- any borrowed int32;
@@ -746,9 +746,9 @@ module Borrows_PartialMove
   BB0 {
     a <- (let (a, _) = x in a);
     x <- (let (a, b) = x in (any Borrows_NonZero_Type.t_nonzero, b));
-    _7 <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * (let (_, a) = x in a)));
+    _7 <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * (let (_, a) = x in a))) (Borrow.inherit_id (Borrow.get_id (let (_, a) = x in a)) 1);
     x <- (let (a, b) = x in (a, { (let (_, a) = x in a) with current = (let Borrows_NonZero_Type.C_NonZero a =  * (let (_, a) = x in a) in Borrows_NonZero_Type.C_NonZero ( ^ _7)) ; }));
-    _6 <- Borrow.borrow_mut ( * _7);
+    _6 <- Borrow.borrow_final ( * _7) (Borrow.get_id _7);
     _7 <- { _7 with current = ( ^ _6) ; };
     _5 <- ([#"../borrows.rs" 55 4 55 20] Inc0.inc _6);
     _6 <- any borrowed int32;
@@ -851,9 +851,9 @@ module Borrows_Destruct
     assert { [@expl:type invariant] Inv0.inv x };
     assume { Resolve0.resolve x };
     a <- (let Borrows_NonZero_Type.C_NonZero a = a in Borrows_NonZero_Type.C_NonZero ([#"../borrows.rs" 63 10 63 11] (0 : int32)));
-    _8 <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * b));
+    _8 <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * b)) (Borrow.inherit_id (Borrow.get_id b) 1);
     b <- { b with current = (let Borrows_NonZero_Type.C_NonZero a =  * b in Borrows_NonZero_Type.C_NonZero ( ^ _8)) ; };
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     _6 <- ([#"../borrows.rs" 64 4 64 17] Inc0.inc _7);
     _7 <- any borrowed int32;
@@ -934,9 +934,9 @@ module Borrows_FrozenDead
     goto BB0
   }
   BB0 {
-    _a <- Borrow.borrow_mut (Borrows_NonZero_Type.nonzero_0 ( * x));
+    _a <- Borrow.borrow_final (Borrows_NonZero_Type.nonzero_0 ( * x)) (Borrow.inherit_id (Borrow.get_id x) 1);
     x <- { x with current = (let Borrows_NonZero_Type.C_NonZero a =  * x in Borrows_NonZero_Type.C_NonZero ( ^ _a)) ; };
-    _6 <- Borrow.borrow_mut ( * y);
+    _6 <- Borrow.borrow_final ( * y) (Borrow.get_id y);
     y <- { y with current = ( ^ _6) ; };
     assume { Inv0.inv ( ^ _6) };
     assert { [@expl:type invariant] Inv1.inv x };
@@ -945,7 +945,7 @@ module Borrows_FrozenDead
     _6 <- any borrowed (Borrows_NonZero_Type.t_nonzero);
     assert { [@expl:type invariant] Inv1.inv x };
     assume { Resolve0.resolve x };
-    _8 <- Borrow.borrow_mut ( * _a);
+    _8 <- Borrow.borrow_final ( * _a) (Borrow.get_id _a);
     _a <- { _a with current = ( ^ _8) ; };
     _7 <- ([#"../borrows.rs" 75 4 75 11] Inc0.inc _8);
     _8 <- any borrowed int32;
@@ -1126,9 +1126,9 @@ module Borrows_Impl3_Foo
     goto BB0
   }
   BB0 {
-    _5 <- Borrow.borrow_mut (Borrows_SumTo10_Type.sumto10_a ( * self));
+    _5 <- Borrow.borrow_final (Borrows_SumTo10_Type.sumto10_a ( * self)) (Borrow.inherit_id (Borrow.get_id self) 1);
     self <- { self with current = (let Borrows_SumTo10_Type.C_SumTo10 a b =  * self in Borrows_SumTo10_Type.C_SumTo10 ( ^ _5) b) ; };
-    _4 <- Borrow.borrow_mut ( * _5);
+    _4 <- Borrow.borrow_final ( * _5) (Borrow.get_id _5);
     _5 <- { _5 with current = ( ^ _4) ; };
     _3 <- ([#"../borrows.rs" 94 8 94 24] Inc0.inc _4);
     _4 <- any borrowed int32;
@@ -1136,9 +1136,9 @@ module Borrows_Impl3_Foo
   }
   BB1 {
     assume { Resolve0.resolve _5 };
-    _8 <- Borrow.borrow_mut (Borrows_SumTo10_Type.sumto10_b ( * self));
+    _8 <- Borrow.borrow_final (Borrows_SumTo10_Type.sumto10_b ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let Borrows_SumTo10_Type.C_SumTo10 a b =  * self in Borrows_SumTo10_Type.C_SumTo10 a ( ^ _8)) ; };
-    _7 <- Borrow.borrow_mut ( * _8);
+    _7 <- Borrow.borrow_final ( * _8) (Borrow.get_id _8);
     _8 <- { _8 with current = ( ^ _7) ; };
     _6 <- ([#"../borrows.rs" 95 8 95 24] Dec0.dec _7);
     _7 <- any borrowed int32;
diff --git a/creusot/tests/should_succeed/unnest.mlcfg b/creusot/tests/should_succeed/unnest.mlcfg
index 45effdb676..62bc4e14ee 100644
--- a/creusot/tests/should_succeed/unnest.mlcfg
+++ b/creusot/tests/should_succeed/unnest.mlcfg
@@ -54,7 +54,7 @@ module Unnest_Unnest
   BB0 {
     _2 <- Borrow.borrow_mut ( *  * x);
     x <- { x with current = { ( * x) with current = ( ^ _2) ; } ; };
-    _0 <- Borrow.borrow_mut ( * _2);
+    _0 <- Borrow.borrow_final ( * _2) (Borrow.get_id _2);
     _2 <- { _2 with current = ( ^ _0) ; };
     assume { Resolve0.resolve _2 };
     assume { Resolve1.resolve x };
diff --git a/creusot/tests/should_succeed/vector/01.mlcfg b/creusot/tests/should_succeed/vector/01.mlcfg
index 8e2ebe6d38..c509c0fa46 100644
--- a/creusot/tests/should_succeed/vector/01.mlcfg
+++ b/creusot/tests/should_succeed/vector/01.mlcfg
@@ -1263,7 +1263,7 @@ module C01_AllZero
   BB7 {
     _21 <- Borrow.borrow_mut iter;
     iter <-  ^ _21;
-    _20 <- Borrow.borrow_mut ( * _21);
+    _20 <- Borrow.borrow_final ( * _21) (Borrow.get_id _21);
     _21 <- { _21 with current = ( ^ _20) ; };
     _19 <- ([#"../01.rs" 9 4 9 42] Next0.next _20);
     _20 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/vector/03_knuth_shuffle.mlcfg b/creusot/tests/should_succeed/vector/03_knuth_shuffle.mlcfg
index 9ad69eda24..72e7f4682d 100644
--- a/creusot/tests/should_succeed/vector/03_knuth_shuffle.mlcfg
+++ b/creusot/tests/should_succeed/vector/03_knuth_shuffle.mlcfg
@@ -1187,7 +1187,7 @@ module C03KnuthShuffle_KnuthShuffle
   BB7 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../03_knuth_shuffle.rs" 16 4 16 43] Next0.next _18);
     _18 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/vector/06_knights_tour.mlcfg b/creusot/tests/should_succeed/vector/06_knights_tour.mlcfg
index d21238a12d..800d9f04f4 100644
--- a/creusot/tests/should_succeed/vector/06_knights_tour.mlcfg
+++ b/creusot/tests/should_succeed/vector/06_knights_tour.mlcfg
@@ -1267,7 +1267,7 @@ module CreusotContracts_Std1_Iter_MapInv_Impl0_Completed
     type self = i
   use CreusotContracts_Std1_Iter_MapInv_MapInv_Type as CreusotContracts_Std1_Iter_MapInv_MapInv_Type
   predicate completed (self : borrowed (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.t_mapinv i Item0.item f)) =
-    [#"../../../../../creusot-contracts/src/std/iter/map_inv.rs" 15 8 18 9] Ghost.inner (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( * self); final = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( ^ self); addr = Borrow.make_new_addr ()} /\ CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( * self) = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( ^ self)
+    [#"../../../../../creusot-contracts/src/std/iter/map_inv.rs" 15 8 18 9] Ghost.inner (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_produced ( ^ self)) = Seq.empty  /\ Completed0.completed {current = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( * self); final = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_iter ( ^ self); id = Borrow.inherit_id (Borrow.get_id self) 1} /\ CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( * self) = CreusotContracts_Std1_Iter_MapInv_MapInv_Type.mapinv_func ( ^ self)
   val completed (self : borrowed (CreusotContracts_Std1_Iter_MapInv_MapInv_Type.t_mapinv i Item0.item f)) : bool
     ensures { result = completed self }
     
@@ -3255,7 +3255,7 @@ module C06KnightsTour_Impl1_CountDegree
   BB8 {
     _19 <- Borrow.borrow_mut iter;
     iter <-  ^ _19;
-    _18 <- Borrow.borrow_mut ( * _19);
+    _18 <- Borrow.borrow_final ( * _19) (Borrow.get_id _19);
     _19 <- { _19 with current = ( ^ _18) ; };
     _17 <- ([#"../06_knights_tour.rs" 73 8 73 46] Next0.next _18);
     _18 <- any borrowed (Alloc_Vec_IntoIter_IntoIter_Type.t_intoiter (isize, isize) (Alloc_Alloc_Global_Type.t_global));
@@ -3620,14 +3620,14 @@ module C06KnightsTour_Impl1_Set
     goto BB0
   }
   BB0 {
-    _12 <- Borrow.borrow_mut (C06KnightsTour_Board_Type.board_field ( * self));
+    _12 <- Borrow.borrow_final (C06KnightsTour_Board_Type.board_field ( * self)) (Borrow.inherit_id (Borrow.get_id self) 2);
     self <- { self with current = (let C06KnightsTour_Board_Type.C_Board a b =  * self in C06KnightsTour_Board_Type.C_Board a ( ^ _12)) ; };
     _11 <- ([#"../06_knights_tour.rs" 88 8 88 32] IndexMut0.index_mut _12 (UIntSize.of_int (IntSize.to_int (C06KnightsTour_Point_Type.point_x p))));
     _12 <- any borrowed (Alloc_Vec_Vec_Type.t_vec (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global)) (Alloc_Alloc_Global_Type.t_global));
     goto BB1
   }
   BB1 {
-    _10 <- Borrow.borrow_mut ( * _11);
+    _10 <- Borrow.borrow_final ( * _11) (Borrow.get_id _11);
     _11 <- { _11 with current = ( ^ _10) ; };
     _9 <- ([#"../06_knights_tour.rs" 88 8 88 46] IndexMut1.index_mut _10 (UIntSize.of_int (IntSize.to_int (C06KnightsTour_Point_Type.point_y p))));
     _10 <- any borrowed (Alloc_Vec_Vec_Type.t_vec usize (Alloc_Alloc_Global_Type.t_global));
@@ -3892,7 +3892,7 @@ module CreusotContracts_Std1_Slice_Impl14_Produces
   predicate produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t)
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 379 12 379 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 380 12 380 66] ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model self) = Seq.(++) visited (ToRefSeq0.to_ref_seq (ShallowModel0.shallow_model tl))
   val produces (self : Core_Slice_Iter_Iter_Type.t_iter t) (visited : Seq.seq t) (tl : Core_Slice_Iter_Iter_Type.t_iter t) : bool
     ensures { result = produces self visited tl }
     
@@ -4067,10 +4067,10 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl_Interface
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   type t
@@ -4079,12 +4079,12 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesRefl
   clone CreusotContracts_Std1_Slice_Impl14_Produces_Stub as Produces0 with
     type t = t
   function produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : () =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 383 4 383 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 384 4 384 10] ()
   val produces_refl (a : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a }
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a }
     ensures { result = produces_refl a }
     
-  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 385 14 385 39] Produces0.produces a (Seq.empty ) a
+  axiom produces_refl_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t . [#"../../../../../creusot-contracts/src/std/slice.rs" 386 14 386 39] Produces0.produces a (Seq.empty ) a
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Stub
   type t
@@ -4112,14 +4112,14 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans_Interface
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   type t
@@ -4134,16 +4134,16 @@ module CreusotContracts_Std1_Slice_Impl14_ProducesTrans
   function produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
     
    =
-    [#"../../../../../creusot-contracts/src/std/slice.rs" 388 4 388 10] ()
+    [#"../../../../../creusot-contracts/src/std/slice.rs" 389 4 389 10] ()
   val produces_trans (a : Core_Slice_Iter_Iter_Type.t_iter t) (ab : Seq.seq t) (b : Core_Slice_Iter_Iter_Type.t_iter t) (bc : Seq.seq t) (c : Core_Slice_Iter_Iter_Type.t_iter t) : ()
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab}
-    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc}
-    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c }
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab}
+    requires {[#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc}
+    ensures { [#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c }
     ensures { result = produces_trans a ab b bc c }
     
-  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 390 15 390 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 31 393 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 61 393 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 14 392 42] Produces0.produces a (Seq.(++) ab bc) c)
+  axiom produces_trans_spec : forall a : Core_Slice_Iter_Iter_Type.t_iter t, ab : Seq.seq t, b : Core_Slice_Iter_Iter_Type.t_iter t, bc : Seq.seq t, c : Core_Slice_Iter_Iter_Type.t_iter t . ([#"../../../../../creusot-contracts/src/std/slice.rs" 391 15 391 32] Produces0.produces a ab b) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 392 15 392 32] Produces0.produces b bc c) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 31 394 33] Inv0.inv ab) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 394 61 394 63] Inv0.inv bc) -> ([#"../../../../../creusot-contracts/src/std/slice.rs" 393 14 393 42] Produces0.produces a (Seq.(++) ab bc) c)
 end
 module C06KnightsTour_Min_Interface
   use prelude.Borrow
@@ -4367,7 +4367,7 @@ module C06KnightsTour_Min
   BB5 {
     _17 <- Borrow.borrow_mut iter;
     iter <-  ^ _17;
-    _16 <- Borrow.borrow_mut ( * _17);
+    _16 <- Borrow.borrow_final ( * _17) (Borrow.get_id _17);
     _17 <- { _17 with current = ( ^ _16) ; };
     _15 <- ([#"../06_knights_tour.rs" 113 4 114 74] Next0.next _16);
     _16 <- any borrowed (Core_Slice_Iter_Iter_Type.t_iter (usize, C06KnightsTour_Point_Type.t_point));
@@ -5154,7 +5154,7 @@ module C06KnightsTour_KnightsTour
   BB10 {
     _37 <- Borrow.borrow_mut iter;
     iter <-  ^ _37;
-    _36 <- Borrow.borrow_mut ( * _37);
+    _36 <- Borrow.borrow_final ( * _37) (Borrow.get_id _37);
     _37 <- { _37 with current = ( ^ _36) ; };
     _35 <- ([#"../06_knights_tour.rs" 142 4 142 36] Next0.next _36);
     _36 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
@@ -5228,7 +5228,7 @@ module C06KnightsTour_KnightsTour
   BB26 {
     _56 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _56;
-    _55 <- Borrow.borrow_mut ( * _56);
+    _55 <- Borrow.borrow_final ( * _56) (Borrow.get_id _56);
     _56 <- { _56 with current = ( ^ _55) ; };
     _54 <- ([#"../06_knights_tour.rs" 148 8 149 54] Next1.next _55);
     _55 <- any borrowed (Alloc_Vec_IntoIter_IntoIter_Type.t_intoiter (isize, isize) (Alloc_Alloc_Global_Type.t_global));
diff --git a/creusot/tests/should_succeed/vector/08_haystack.mlcfg b/creusot/tests/should_succeed/vector/08_haystack.mlcfg
index 108f9a99ec..fc193634d1 100644
--- a/creusot/tests/should_succeed/vector/08_haystack.mlcfg
+++ b/creusot/tests/should_succeed/vector/08_haystack.mlcfg
@@ -1978,7 +1978,7 @@ module C08Haystack_Search
   BB8 {
     _26 <- Borrow.borrow_mut iter;
     iter <-  ^ _26;
-    _25 <- Borrow.borrow_mut ( * _26);
+    _25 <- Borrow.borrow_final ( * _26) (Borrow.get_id _26);
     _26 <- { _26 with current = ( ^ _25) ; };
     _24 <- ([#"../08_haystack.rs" 22 4 22 112] Next0.next _25);
     _25 <- any borrowed (Core_Ops_Range_RangeInclusive_Type.t_rangeinclusive usize);
@@ -2038,7 +2038,7 @@ module C08Haystack_Search
   BB20 {
     _47 <- Borrow.borrow_mut iter1;
     iter1 <-  ^ _47;
-    _46 <- Borrow.borrow_mut ( * _47);
+    _46 <- Borrow.borrow_final ( * _47) (Borrow.get_id _47);
     _47 <- { _47 with current = ( ^ _46) ; };
     _45 <- ([#"../08_haystack.rs" 24 8 24 68] Next1.next _46);
     _46 <- any borrowed (Core_Ops_Range_Range_Type.t_range usize);
diff --git a/creusot/tests/should_succeed/vector/09_capacity.mlcfg b/creusot/tests/should_succeed/vector/09_capacity.mlcfg
index eab3800bfd..7e3a9c8d06 100644
--- a/creusot/tests/should_succeed/vector/09_capacity.mlcfg
+++ b/creusot/tests/should_succeed/vector/09_capacity.mlcfg
@@ -540,7 +540,7 @@ module C09Capacity_ChangeCapacity
     goto BB3
   }
   BB3 {
-    _11 <- Borrow.borrow_mut ( * v);
+    _11 <- Borrow.borrow_final ( * v) (Borrow.get_id v);
     v <- { v with current = ( ^ _11) ; };
     assume { Inv0.inv ( ^ _11) };
     _10 <- ([#"../09_capacity.rs" 10 4 10 18] ShrinkTo0.shrink_to _11 ([#"../09_capacity.rs" 10 16 10 17] (1 : usize)));
@@ -663,7 +663,7 @@ module C09Capacity_ClearVec
     goto BB0
   }
   BB0 {
-    _4 <- Borrow.borrow_mut ( * v);
+    _4 <- Borrow.borrow_final ( * v) (Borrow.get_id v);
     v <- { v with current = ( ^ _4) ; };
     assume { Inv0.inv ( ^ _4) };
     _3 <- ([#"../09_capacity.rs" 15 4 15 13] Clear0.clear _4);