implement reset groups

include/ctre/actions/capture.inc.hpp

@@ -36,5 +36,139 @@ template <auto... Str, auto V, typename... Content, size_t Id, typename... Ts, s
 	return pcre_context{ctll::push_front(capture_with_name<Id, id<Str...>, Content...>(), ctll::list<Ts...>()), pcre_parameters<Counter>()};
 }
 
+template<size_t To, auto... Str, typename T>
+static constexpr auto replace_captures_with_id(T, string<Str...>) { // fallback case, no transform
+	return T{};
+}
+
+template<size_t To, auto... Str, size_t From, typename... Content>
+static constexpr auto replace_captures_with_id(capture<From, Content...>, string<Str...>) {
+	return capture<To, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+// named reseted captures must have same Str... for all instances inside the call (otherwise how would we know how to access which by name?)
+template<size_t To, auto... Str, size_t From, auto... Str2, typename... Content>
+static constexpr auto replace_captures_with_id(capture_with_name<From, id<Str2...>, Content...>, string<Str...>) {
+	static_assert((id<Str...>{} == id<Str2...>{}) && "named captures must be the same");
+	return capture_with_name<From, id<Str...>, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, typename... Content>
+static constexpr auto replace_captures_with_id(sequence<Content...>, string<Str...>) {
+	return sequence<decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, size_t Id, typename... Content>
+static constexpr auto replace_captures_with_id(reset_group<Id, Content...>, string<Str...>) {
+	return reset_group<To, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, size_t Id, auto... Str2, typename... Content>
+static constexpr auto replace_captures_with_id(reset_group_with_name<Id, id<Str2...>, Content...>, string<Str...>) {
+	return reset_group_with_name<To, id<Str...>, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, typename... Content>
+static constexpr auto replace_captures_with_id(atomic_group<Content...>, string<Str...>) {
+	return atomic_group<decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, typename... Content>
+static constexpr auto replace_captures_with_id(lookahead_positive<Content...>, string<Str...>) {
+	return lookahead_positive<decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, typename... Content>
+static constexpr auto replace_captures_with_id(lookahead_negative<Content...>, string<Str...>) {
+	return lookahead_negative<decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, size_t A, size_t B, typename... Content>
+static constexpr auto replace_captures_with_id(possessive_repeat<A, B, Content...>, string<Str...>) {
+	return possessive_repeat<A, B, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, size_t A, size_t B, typename... Content>
+static constexpr auto replace_captures_with_id(repeat<A, B, Content...>, string<Str...>) {
+	return repeat<A, B, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, size_t A, size_t B, typename... Content>
+static constexpr auto replace_captures_with_id(lazy_repeat<A, B, Content...>, string<Str...>) {
+	return lazy_repeat<A, B, decltype(replace_captures_with_id<To>(Content{}, string<Str...>{}))...>{};
+}
+
+template<size_t To, auto... Str, typename... Opts>
+static constexpr auto replace_captures_with_id(select<Opts...>, string<Str...>) {
+	return select<decltype(replace_captures_with_id<To>(Opts{}, string<Str...>{}))...>{};
+}
+
+// get name (might be a utility already written)
+template<size_t Idx, auto... Str>
+static constexpr string<Str...> get_capture_name(captured_content<Idx, id<Str...>>) noexcept {
+	return string<Str...>{};
+}
+
+template<size_t Idx>
+static constexpr string<> get_capture_name(captured_content<Idx>) noexcept {
+	return string<>{};
+}
+
+template<auto... Str>
+static constexpr id<Str...> make_id_from_string(string<Str...>) noexcept {
+	return id<Str...>{};
+}
+
+// find the first named capture
+template<typename H, typename... Tail>
+static constexpr auto get_capture_with_name(ctll::list<H, Tail...>) noexcept {
+	if constexpr (sizeof...(Tail))
+		return get_capture_with_name(ctll::list<Tail...>{});
+	else
+		return ctll::list<>{};
+}
+
+template<size_t Idx, typename Name, typename... Tail>
+static constexpr auto get_capture_with_name(ctll::list<captured_content<Idx, Name>, Tail...>) noexcept {
+	return ctll::list<captured_content<Idx, Name>>{};
+}
+
+// reset group start
+template <auto V, typename... Ts, size_t Counter> static constexpr auto apply(pcre::start_reset_group, ctll::term<V>, pcre_context<ctll::list<Ts...>, pcre_parameters<Counter>>) {
+	return pcre_context{ ctll::push_front(reset_start<Counter+1>(), ctll::list<Ts...>()), pcre_parameters<Counter>() };
+		//ctll::list<reset_start<Counter+1>(), Ts...>(),  };
+}
+
+// reset group end
+template <auto V, typename A, typename... Ts, size_t Id, size_t Counter> static constexpr auto apply(pcre::make_reset_group, ctll::term<V>, pcre_context<ctll::list<A, reset_start<Id>, Ts...>, pcre_parameters<Counter>>) {
+	using first_capture = decltype(ctll::front(find_captures(A{})));
+	if constexpr (::std::is_same_v<first_capture, ctll::_nothing>) {
+		//no captures to reset... easy case
+		return pcre_context{ ctll::list<sequence<A>, Ts...>(), pcre_parameters<Counter>() };
+	} else {
+		using first_named_capture = decltype(ctll::front(get_capture_with_name(find_captures(A{}))));
+		if constexpr (::std::is_same_v<first_named_capture, ctll::_nothing>) {
+			return pcre_context{ ctll::list<reset_group<Id, decltype(replace_captures_with_id<Id>(A{}, string<>{}))>, Ts...>(), pcre_parameters<Counter>() };
+		} else {
+			return pcre_context{ ctll::list<reset_group_with_name<Id, decltype(make_id_from_string(get_capture_name(first_named_capture{}))), decltype(replace_captures_with_id<Id>(A{}, get_capture_name(first_named_capture{})))>, Ts...>(), pcre_parameters<Counter>() };
+		}
+	}
+}
+// reset group end (sequence)
+template <auto V, typename... Content, typename... Ts, size_t Id, size_t Counter> static constexpr auto apply(pcre::make_reset_group, ctll::term<V>, pcre_context<ctll::list<ctre::sequence<Content...>, reset_start<Id>, Ts...>, pcre_parameters<Counter>>) {
+	using first_capture = decltype(ctll::front(find_captures(sequence<Content...>{})));
+	if constexpr (::std::is_same_v<first_capture, ctll::_nothing>) {
+		//no captures to reset... easy case
+		return pcre_context{ ctll::list<sequence<Content...>, Ts...>(), pcre_parameters<Counter>() };
+	} else {
+		using first_named_capture = decltype(ctll::front(get_capture_with_name(find_captures(sequence<Content...>{}))));
+		if constexpr (::std::is_same_v<first_named_capture, ctll::_nothing>) {
+			return pcre_context{ ctll::list<reset_group<Id, decltype(replace_captures_with_id<Id>(Content{}, string<>{}))...>, Ts...>(), pcre_parameters<Counter>() };
+		} else {
+			return pcre_context{ ctll::list<reset_group<Id, decltype(make_id_from_string(get_capture_name(first_named_capture{}))), decltype(replace_captures_with_id<Id>(Content{}, get_capture_name(first_named_capture{})))...>, Ts...>(), pcre_parameters<Counter>() };
+		}
+	}
+}
+
+
 
 #endif

include/ctre/atoms.hpp

@@ -42,9 +42,13 @@ template <size_t Index, typename... Content> struct capture { };
 
 template <size_t Index, typename Name, typename... Content> struct capture_with_name { };
 
+template <size_t Index, typename... Content> struct reset_group { };
+template <size_t Index, typename Name, typename... Content> struct reset_group_with_name { };
+
 template <size_t Index> struct back_reference { };
 template <typename Name> struct back_reference_with_name { };
 
+template <size_t Idx> struct reset_start { };
 template <typename Type> struct look_start { };
 
 template <typename... Content> struct lookahead_positive { };

include/ctre/evaluation.hpp

@@ -159,6 +159,16 @@ constexpr CTRE_FORCE_INLINE R evaluate(const Iterator begin, Iterator current, c
 	}
 }
 
+template <typename R, typename Iterator, typename EndIterator, size_t Id, typename... Content, typename... Tail> 
+constexpr CTRE_FORCE_INLINE R evaluate(const Iterator begin, Iterator current, const EndIterator end, const flags & f, R captures, ctll::list<reset_group<Id, Content...>, Tail...>) noexcept {
+	return evaluate(begin, current, end, f, captures, ctll::list<sequence<Content...>, Tail...>{});
+}
+
+template <typename R, typename Iterator, typename EndIterator, size_t Id, typename Name, typename... Content, typename... Tail>
+constexpr CTRE_FORCE_INLINE R evaluate(const Iterator begin, Iterator current, const EndIterator end, const flags& f, R captures, ctll::list<reset_group_with_name<Id, Name, Content...>, Tail...>) noexcept {
+	return evaluate(begin, current, end, f, captures, ctll::list<sequence<Content...>, Tail...>{});
+}
+
 // matching empty in patterns
 template <typename R, typename Iterator, typename EndIterator, typename... Tail> 
 constexpr CTRE_FORCE_INLINE R evaluate(const Iterator begin, Iterator current, const EndIterator end, const flags & f, R captures, ctll::list<empty, Tail...>) noexcept {

include/ctre/find_captures.hpp

@@ -120,6 +120,13 @@ template <size_t Id, typename Name, typename... Content, typename... Tail, typen
 	return find_captures(ctll::list<Content..., Tail...>(), ctll::list<Output..., captured_content<Id, Name>>());
 }
 
+template <size_t Id, typename... Content, typename... Tail, typename... Output> constexpr auto find_captures(ctll::list<reset_group<Id, Content...>, Tail...>, ctll::list<Output...>) noexcept {
+	return find_captures(ctll::list<Content..., Tail...>(), ctll::list<Output..., captured_content<Id>>());
+}
+
+template <size_t Id, typename Name, typename... Content, typename... Tail, typename... Output> constexpr auto find_captures(ctll::list<reset_group_with_name<Id, Name, Content...>, Tail...>, ctll::list<Output...>) noexcept {
+	return find_captures(ctll::list<Content..., Tail...>(), ctll::list<Output..., captured_content<Id, Name>>());
+}
 
 
 }

include/ctre/first.hpp

@@ -178,6 +178,17 @@ constexpr auto first(ctll::list<Content...> l, ctll::list<capture_with_name<Id,
 	return first(l, ctll::list<Seq..., Tail...>{});
 }
 
+// reset groups
+template <typename... Content, size_t Id, typename... Seq, typename... Tail>
+constexpr auto first(ctll::list<Content...> l, ctll::list<reset_group<Id, Seq...>, Tail...>) noexcept {
+	return first(l, ctll::list<Seq..., Tail...>{});
+}
+
+template <typename... Content, size_t Id, typename Name, typename... Seq, typename... Tail>
+constexpr auto first(ctll::list<Content...> l, ctll::list<reset_group_with_name<Id, Name, Seq...>, Tail...>) noexcept {
+	return first(l, ctll::list<Seq..., Tail...>{});
+}
+
 // backreference
 template <typename... Content, size_t Id, typename... Tail> 
 constexpr auto first(ctll::list<Content...>, ctll::list<back_reference<Id>, Tail...>) noexcept {

include/ctre/pcre.hpp

@@ -93,6 +93,7 @@ struct pcre {
 	struct make_property: ctll::action {};
 	struct make_property_negative: ctll::action {};
 	struct make_range: ctll::action {};
+	struct make_reset_group: ctll::action {};
 	struct make_relative_back_reference: ctll::action {};
 	struct make_sequence: ctll::action {};
 	struct negate_class_named: ctll::action {};
@@ -132,6 +133,7 @@ struct pcre {
 	struct start_atomic: ctll::action {};
 	struct start_lookahead_negative: ctll::action {};
 	struct start_lookahead_positive: ctll::action {};
+	struct start_reset_group: ctll::action {};
 
 // (q)LL1 function:
 	using _others = ctll::neg_set<'!','$','\x28','\x29','*','+',',','-','.',':','<','=','>','?','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','[','\\',']','^','_','a','b','c','d','e','f','g','h','0','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','\x7B','|','\x7D','1','2','3','4','5','6','7','8','9'>;
@@ -272,6 +274,7 @@ struct pcre {
 	static constexpr auto rule(d, ctll::term<'>'>) -> ctll::push<reset_capture, ctll::anything, start_atomic, content_in_capture, make_atomic, ctll::term<'\x29'>>;
 	static constexpr auto rule(d, ctll::term<'!'>) -> ctll::push<reset_capture, ctll::anything, start_lookahead_negative, content_in_capture, look_finish, ctll::term<'\x29'>>;
 	static constexpr auto rule(d, ctll::term<'='>) -> ctll::push<reset_capture, ctll::anything, start_lookahead_positive, content_in_capture, look_finish, ctll::term<'\x29'>>;
+	static constexpr auto rule(d, ctll::term<'|'>) -> ctll::push<reset_capture, ctll::anything, start_reset_group, content_in_capture, make_reset_group, ctll::term<'\x29'>>;
 
 	static constexpr auto rule(e, ctll::term<'d'>) -> ctll::push<ctll::anything, class_digit>;
 	static constexpr auto rule(e, ctll::term<'h'>) -> ctll::push<ctll::anything, class_horizontal_space>;

include/ctre/pcre_actions.hpp

@@ -5,6 +5,8 @@
 #include "atoms.hpp"
 #include "atoms_unicode.hpp"
 #include "id.hpp"
+#include "first.hpp"
+#include "return_type.hpp"
 #include <cstdint>
 #include <limits>
 

tests/generating.cpp

@@ -208,6 +208,9 @@ static_assert(same_f(CTRE_GEN("(((a)(b)))"),ctre::capture<1, ctre::capture<2,ctr
 
 static_assert(same_f(CTRE_GEN("((?:a)(b))"), ctre::capture<1,ctre::character<'a'>,ctre::capture<2,ctre::character<'b'>>>()));
 
+// reset groups
+static_assert(same_f(CTRE_GEN("(?|(?<name>a)|(b))"), ctre::reset_group_with_name<1,ctre::id<'n','a','m','e'>,ctre::select<ctre::capture_with_name<1,ctre::id<'n','a','m','e'>, ctre::character<'a'>>,ctre::capture<1, ctre::character<'b'>>>>()));
+static_assert(same_f(CTRE_GEN("(?|(b)|(a))"), ctre::reset_group<1,ctre::select<ctre::capture<1, ctre::character<'b'>>, ctre::capture<1, ctre::character<'a'>>>>()));
 
 // backreference
 static_assert(same_f(CTRE_GEN("(a)\\g{1}"), ctre::sequence<ctre::capture<1,ctre::character<'a'>>, ctre::back_reference<1>>()));