[libc++] Implement ranges::for_each{, _n}
Reviewed By: var-const, #libc
Spies: libcxx-commits, mgorny
Differential Revision: https://reviews.llvm.org/D124332
NOKEYCHECK=True
GitOrigin-RevId: 80045e9afa2f3545d3b1f2d06090a9a053a90307
diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index 423a1ff..257e9d5 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -75,6 +75,8 @@
__algorithm/ranges_find.h
__algorithm/ranges_find_if.h
__algorithm/ranges_find_if_not.h
+ __algorithm/ranges_for_each.h
+ __algorithm/ranges_for_each_n.h
__algorithm/ranges_max.h
__algorithm/ranges_max_element.h
__algorithm/ranges_min.h
diff --git a/include/__algorithm/ranges_for_each.h b/include/__algorithm/ranges_for_each.h
new file mode 100644
index 0000000..f284c0e
--- /dev/null
+++ b/include/__algorithm/ranges_for_each.h
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
+#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
+
+#include <__algorithm/in_fun_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Func>
+using for_each_result = in_fun_result<_Iter, _Func>;
+
+namespace __for_each {
+struct __fn {
+private:
+ template <class _Iter, class _Sent, class _Proj, class _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr static
+ for_each_result<_Iter, _Func> __for_each_impl(_Iter __first, _Sent __last, _Func& __func, _Proj& __proj) {
+ for (; __first != __last; ++__first)
+ std::invoke(__func, std::invoke(__proj, *__first));
+ return {std::move(__first), std::move(__func)};
+ }
+
+public:
+ template <input_iterator _Iter, sentinel_for<_Iter> _Sent,
+ class _Proj = identity,
+ indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ for_each_result<_Iter, _Func> operator()(_Iter __first, _Sent __last, _Func __func, _Proj __proj = {}) const {
+ return __for_each_impl(std::move(__first), std::move(__last), __func, __proj);
+ }
+
+ template <input_range _Range,
+ class _Proj = identity,
+ indirectly_unary_invocable<projected<iterator_t<_Range>, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ for_each_result<borrowed_iterator_t<_Range>, _Func> operator()(_Range&& __range,
+ _Func __func,
+ _Proj __proj = {}) const {
+ return __for_each_impl(ranges::begin(__range), ranges::end(__range), __func, __proj);
+ }
+
+};
+} // namespace __for_each
+
+inline namespace __cpo {
+ inline constexpr auto for_each = __for_each::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
diff --git a/include/__algorithm/ranges_for_each_n.h b/include/__algorithm/ranges_for_each_n.h
new file mode 100644
index 0000000..f40f849
--- /dev/null
+++ b/include/__algorithm/ranges_for_each_n.h
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
+#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
+
+#include <__algorithm/in_fun_result.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__iterator/concepts.h>
+#include <__iterator/incrementable_traits.h>
+#include <__iterator/projected.h>
+#include <__ranges/concepts.h>
+#include <__ranges/dangling.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <class _Iter, class _Func>
+using for_each_n_result = in_fun_result<_Iter, _Func>;
+
+namespace __for_each_n {
+struct __fn {
+
+ template <input_iterator _Iter,
+ class _Proj = identity,
+ indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ for_each_n_result<_Iter, _Func> operator()(_Iter __first,
+ iter_difference_t<_Iter> __count,
+ _Func __func,
+ _Proj __proj = {}) const {
+ while (__count-- > 0) {
+ std::invoke(__func, std::invoke(__proj, *__first));
+ ++__first;
+ }
+ return {std::move(__first), std::move(__func)};
+ }
+
+};
+} // namespace __for_each_n
+
+inline namespace __cpo {
+ inline constexpr auto for_each_n = __for_each_n::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
diff --git a/include/algorithm b/include/algorithm
index 2c1474e..13b3064 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -238,6 +238,24 @@
requires indirectly_copyable<iterator_t<R>, I>
constexpr ranges::copy_backward_result<borrowed_iterator_t<R>, I>
ranges::copy_backward(R&& r, I result); // since C++20
+
+ template<class I, class F>
+ using for_each_result = in_fun_result<I, F>; // since C++20
+
+ template<input_iterator I, sentinel_for<I> S, class Proj = identity,
+ indirectly_unary_invocable<projected<I, Proj>> Fun>
+ constexpr ranges::for_each_result<I, Fun>
+ ranges::for_each(I first, S last, Fun f, Proj proj = {}); // since C++20
+
+ template<input_range R, class Proj = identity,
+ indirectly_unary_invocable<projected<iterator_t<R>, Proj>> Fun>
+ constexpr ranges::for_each_result<borrowed_iterator_t<R>, Fun>
+ ranges::for_each(R&& r, Fun f, Proj proj = {}); // since C++20
+
+ template<input_iterator I, class Proj = identity,
+ indirectly_unary_invocable<projected<I, Proj>> Fun>
+ constexpr ranges::for_each_n_result<I, Fun>
+ ranges::for_each_n(I first, iter_difference_t<I> n, Fun f, Proj proj = {}); // since C++20
}
constexpr bool // constexpr in C++20
@@ -963,6 +981,8 @@
#include <__algorithm/ranges_find.h>
#include <__algorithm/ranges_find_if.h>
#include <__algorithm/ranges_find_if_not.h>
+#include <__algorithm/ranges_for_each.h>
+#include <__algorithm/ranges_for_each_n.h>
#include <__algorithm/ranges_max.h>
#include <__algorithm/ranges_max_element.h>
#include <__algorithm/ranges_min.h>
diff --git a/include/module.modulemap b/include/module.modulemap
index f6a7179..c027bdc 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -303,6 +303,8 @@
module ranges_find { private header "__algorithm/ranges_find.h" }
module ranges_find_if { private header "__algorithm/ranges_find_if.h" }
module ranges_find_if_not { private header "__algorithm/ranges_find_if_not.h" }
+ module ranges_for_each { private header "__algorithm/ranges_for_each.h" }
+ module ranges_for_each_n { private header "__algorithm/ranges_for_each_n.h" }
module ranges_max { private header "__algorithm/ranges_max.h" }
module ranges_max_element { private header "__algorithm/ranges_max_element.h" }
module ranges_min { private header "__algorithm/ranges_min.h" }