From 540c902e62f3756bf61e625e781b7fbf409cb18c Mon Sep 17 00:00:00 2001
From: Jay Lee <jaeho.lee@snu.ac.kr>
Date: Fri, 5 Jul 2024 15:09:10 +0900
Subject: [PATCH] :sparkles: SEQ parsing

---
 .ocamlformat-ignore |  1 +
 lib/lexer.mll       |  4 ++--
 lib/parser.mly      | 15 ++++++++++++---
 samples/simple.ml   |  2 +-
 4 files changed, 16 insertions(+), 6 deletions(-)
 create mode 100644 .ocamlformat-ignore

diff --git a/.ocamlformat-ignore b/.ocamlformat-ignore
new file mode 100644
index 0000000..781fb73
--- /dev/null
+++ b/.ocamlformat-ignore
@@ -0,0 +1 @@
+samples/*
diff --git a/lib/lexer.mll b/lib/lexer.mll
index e77a46f..d6d0beb 100644
--- a/lib/lexer.mll
+++ b/lib/lexer.mll
@@ -62,8 +62,8 @@ rule read =
   | '['       { LBRACK }
   | ']'       { RBRACK }
   | ','       { COMMA }
-  | ';'       { SEMICOLON }
-  | ";;"      { COMPEND }
+  | ';'       { SEMI }
+  | ";;"      { SEMISEMI }
   | eof       { EOF }
   | _         { raise (SyntaxError ("Unexpected char: " ^ lexeme lexbuf)) }
 
diff --git a/lib/parser.mly b/lib/parser.mly
index 367b7fb..2dd7366 100644
--- a/lib/parser.mly
+++ b/lib/parser.mly
@@ -14,9 +14,13 @@ open Expr
 %token AND OR
 %token PLUS MINUS TIMES
 %token LPAREN RPAREN LBRACK RBRACK
-%token RARROW COMMA SEMICOLON COMPEND
+%token RARROW COMMA SEMI SEMISEMI
 %token EOF
 
+%nonassoc RARROW
+%nonassoc IN
+%right    SEMI
+%nonassoc EFF
 %nonassoc THEN /* below ELSE (if ... then ...) */
 %nonassoc ELSE /* (if ... then ... else ...) */
 %right    OR
@@ -31,7 +35,7 @@ prog:
     | prog = comp_lst; EOF { prog }
 comp_lst:
     | e = expr { Expr (hook_free_exn e) }
-    | c = comp_expr; COMPEND; tl = comp_lst { Comp (c, tl) } ;
+    | c = comp_expr; SEMISEMI; tl = comp_lst { Comp (c, tl) } ;
 comp_expr:
     | LET; name = var; param = var; EQ; body = expr { { name; param; body = hook_full body } }
 expr:
@@ -44,12 +48,17 @@ expr:
     | STT; stt = var; COMMA; set = var; EQ; init = expr; IN; body = expr
       { Ex (Stt { label = -1; stt; set; init = hook_free_exn init; body = hook_full body }) }
     | EFF; e = expr { Ex (Eff (hook_free_exn e)) }
-    | VIEW; LBRACK; vss = separated_nonempty_list(SEMICOLON, expr); RBRACK { Ex (View (List.map hook_free_exn vss)) }
+    | VIEW; LBRACK; vss = separated_nonempty_list(COMMA, expr); RBRACK { Ex (View (List.map hook_free_exn vss)) }
     | fn = atom; arg = atom { Ex (App { fn = hook_free_exn fn; arg = hook_free_exn arg }) }
     | IF; pred = expr; THEN; con = expr; ELSE; alt = expr
       { Ex (Cond { pred = hook_free_exn pred; con = hook_free_exn con; alt = hook_free_exn alt }) }
     | IF; pred = expr; THEN; con = expr
       { Ex (Cond { pred = hook_free_exn pred; con = hook_free_exn con; alt = Const Unit }) }
+    | e1 = expr; SEMI; e2 = expr
+      { match hook_free e1, hook_free e2 with
+        | Some e1, Some e2 -> Ex (Seq (e1, e2))
+        | _, _ -> Ex (Seq (hook_full e1, hook_full e2))
+      }
 bop_expr:
     | atom { $1 }
     | left = bop_expr; op = op; right = bop_expr
diff --git a/samples/simple.ml b/samples/simple.ml
index 179386d..7958474 100644
--- a/samples/simple.ml
+++ b/samples/simple.ml
@@ -1,6 +1,6 @@
 let C x =
   stt s, setS = 42 in
-  # eff (setS (fun s -> 43));
+  eff (setS (fun s -> 43));
   view [()]
 ;;
 view [C ()]