This is a snapshot of work on P2714 "Bind front and back to NTTP
callables", posted for reference. Not tested.
libstdc++-v3/ChangeLog:
PR libstdc++/119744
* include/bits/version.def: Redefine __cpp_lib_bind_front etc.
* include/bits/version.h: Ditto.
* include/std/functional: Add new bind_front etc. overloads
---
libstdc++-v3/include/bits/version.def | 6 +-
libstdc++-v3/include/bits/version.h | 18 ++---
libstdc++-v3/include/std/functional | 96 ++++++++++++++++++++++++++-
3 files changed, 107 insertions(+), 13 deletions(-)
diff --git a/libstdc++-v3/include/bits/version.def
b/libstdc++-v3/include/bits/version.def
index b89b287e8e8..f8ccfaeb8c3 100644
--- a/libstdc++-v3/include/bits/version.def
+++ b/libstdc++-v3/include/bits/version.def
@@ -464,7 +464,7 @@ ftms = {
ftms = {
name = not_fn;
values = {
- v = 201603;
+ v = 202306;
cxxmin = 17;
};
};
@@ -777,7 +777,7 @@ ftms = {
ftms = {
name = bind_front;
values = {
- v = 201907;
+ v = 202306
cxxmin = 20;
};
};
@@ -785,7 +785,7 @@ ftms = {
ftms = {
name = bind_back;
values = {
- v = 202202;
+ v = 202306;
cxxmin = 23;
extra_cond = "__cpp_explicit_this_parameter";
};
diff --git a/libstdc++-v3/include/bits/version.h
b/libstdc++-v3/include/bits/version.h
index a70a7ede68c..52e6ae2d9b8 100644
--- a/libstdc++-v3/include/bits/version.h
+++ b/libstdc++-v3/include/bits/version.h
@@ -511,10 +511,10 @@
#undef __glibcxx_want_make_from_tuple
#if !defined(__cpp_lib_not_fn)
-# if (__cplusplus >= 201703L)
-# define __glibcxx_not_fn 201603L
+# if (__cplusplus >= 202306L)
+# define __glibcxx_not_fn 202306L
# if defined(__glibcxx_want_all) || defined(__glibcxx_want_not_fn)
-# define __cpp_lib_not_fn 201603L
+# define __cpp_lib_not_fn 202306L
# endif
# endif
#endif /* !defined(__cpp_lib_not_fn) && defined(__glibcxx_want_not_fn) */
@@ -866,20 +866,20 @@
#undef __glibcxx_want_atomic_value_initialization
#if !defined(__cpp_lib_bind_front)
-# if (__cplusplus >= 202002L)
-# define __glibcxx_bind_front 201907L
+# if (__cplusplus >= 202306L)
+# define __glibcxx_bind_front 202306L
# if defined(__glibcxx_want_all) || defined(__glibcxx_want_bind_front)
-# define __cpp_lib_bind_front 201907L
+# define __cpp_lib_bind_front 202306L
# endif
# endif
#endif /* !defined(__cpp_lib_bind_front) && defined(__glibcxx_want_bind_front)
*/
#undef __glibcxx_want_bind_front
#if !defined(__cpp_lib_bind_back)
-# if (__cplusplus >= 202100L) && (__cpp_explicit_this_parameter)
-# define __glibcxx_bind_back 202202L
+# if (__cplusplus >= 202306L) && (__cpp_explicit_this_parameter)
+# define __glibcxx_bind_back 202306L
# if defined(__glibcxx_want_all) || defined(__glibcxx_want_bind_back)
-# define __cpp_lib_bind_back 202202L
+# define __cpp_lib_bind_back 202306L
# endif
# endif
#endif /* !defined(__cpp_lib_bind_back) && defined(__glibcxx_want_bind_back) */
diff --git a/libstdc++-v3/include/std/functional
b/libstdc++-v3/include/std/functional
index 307bcb95bcc..c317d471350 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -940,7 +940,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_bound_args(std::forward<_Args>(__args)...)
{ static_assert(sizeof...(_Args) == sizeof...(_BoundArgs)); }
-#if __cpp_explicit_this_parameter
+#ifdef __cpp_explicit_this_parameter
template<typename _Self, typename... _CallArgs>
constexpr
invoke_result_t<__like_t<_Self, _Fd>, __like_t<_Self, _BoundArgs>...,
_CallArgs...>
@@ -1049,6 +1049,97 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
return _Bind_front_t<_Fn, _Args...>(0, std::forward<_Fn>(__fn),
std::forward<_Args>(__args)...);
}
+
+#if __cpp_lib_bind_front >= 202306
+
+ template<typename _T, typename _U>
+ struct __copy_const : conditional<is_const_v<_T>, const _U, _U> {};
+
+ template<typename _T, typename _U,
+ class _X = __copy_const<remove_reference_t<_T>, _U>::type>
+
+ struct __copy_value_category
+ : conditional<is_lvalue_reference_v<_T&&>, _X&, _X&&>
+ {};
+
+ template<typename _T, typename _U>
+ struct __type_forward_like : __copy_value_category<_T,
remove_reference_t<_U>>
+ {};
+
+ template<typename _T, typename _U>
+ using __type_forward_like_t = __type_forward_like<_T, _U>::type;
+
+ /** Create call wrapper by partial application of arguments to function.
+ *
+ * The result of `std::bind_front<f>(args...)` is a function object that
+ * stores `f` and the bound arguments, `args...`. When that function
+ * object is invoked with `call_args...` it returns the result of calling
+ * `f(args..., call_args...)`.
+ *
+ * @since C++26
+ */
+
+ template<auto __fn, typename... _Args>
+ constexpr auto
+ bind_front(_Args&&... __args)
+ requires (
+ (is_constructible_v<decay_t<_Args>, _Args> and ...) and
+ (is_move_constructible_v<decay_t<_Args>> and ...))
+ {
+ using _Fn = decltype(__fn);
+ if constexpr (is_pointer_v<_Fn> or is_member_pointer_v<_Fn>) {
+ static_assert(__fn != nullptr);
+ }
+ return [... __bound_args(std::forward<_Args>(__args))]<
+ typename _Self, typename... _T>
+ (this _Self&&, _T&&... __call_args)
+ noexcept(is_nothrow_invocable_v<
+ _Fn, __type_forward_like_t<_Self, decay_t<_Args>>..., _T...>)
+ -> invoke_result_t<
+ _Fn, __type_forward_like_t<_Self, decay_t<_Args>>..., _T...>
+ {
+ return invoke(__fn,
+ forward_like<_Self>(__bound_args)...,
+ forward<_T>(__call_args)...);
+ };
+ }
+
+ /** Create call wrapper by partial application of arguments to function.
+ *
+ * The result of `std::bind_back<f>(args...)` is a function object that
+ * stores `f` and the bound arguments, `args...`. When that function
+ * object is invoked with `call_args...` it returns the result of calling
+ * `f(call_args..., args...)`.
+ *
+ * @since C++26
+ */
+
+ template<auto __fn, typename... _Args>
+ constexpr auto
+ bind_back(_Args&&... __args)
+ requires (
+ (is_constructible_v<decay_t<_Args>, _Args> and ...) and
+ (is_move_constructible_v<decay_t<_Args>> and ...))
+ {
+ using _Fn = decltype(__fn);
+ if constexpr (is_pointer_v<_Fn> or is_member_pointer_v<_Fn>) {
+ static_assert(__fn != nullptr);
+ }
+ return [... __bound_args(std::forward<_Args>(__args))]<
+ typename _Self, typename... _T>
+ (this _Self&&, _T&&... __call_args)
+ noexcept(is_nothrow_invocable_v<
+ _Fn, __type_forward_like_t<_Self, decay_t<_Args>>..., _T...>)
+ -> invoke_result_t<
+ _Fn, __type_forward_like_t<_Self, decay_t<_Args>>..., _T...>
+ {
+ return invoke(__fn,
+ forward<_T>(__call_args)...,
+ forward_like<_Self>(__bound_args)...);
+ };
+ }
+
+#endif // __cpp_lib_bind_front >= 202306, NTTP bind_front
#endif // __cpp_lib_bind_front
#ifdef __cpp_lib_bind_back // C++ >= 23
@@ -1216,6 +1307,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
not_fn(_Fn&& __fn)
noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
{
+ if constexpr (is_pointer_v<_Fn> || is_member_pointer_v<_Fn>) {
+ static_assert(__fn != nullptr);
+ }
return _Not_fn<std::decay_t<_Fn>>{std::forward<_Fn>(__fn), 0};
}
#endif
--
2.50.0
