[libc++][P1115][C++20] Improving the Return Value of Erase-Like Algorithms II: Free erase/erase if.
Summary:
This patch adds return type to std::erase and std::erase_if functions.
Also:
* Update __cpp_lib_erase_if to 202002L.
* Fix synopsis in unordered_map.
* Fix generate_feature_test_macro_components.py script.
Reviewers: EricWF, mclow.lists, ldionne, #libc
Reviewed By: ldionne, #libc
Subscribers: broadwaylamb, zoecarver, dexonsmith, ldionne, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D75905
Cr-Mirrored-From: https://chromium.googlesource.com/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 3e895085de0afdd85574b35de48a1bcc6544f2ec
diff --git a/include/vector b/include/vector
index af96bff..7d0fec8 100644
--- a/include/vector
+++ b/include/vector
@@ -261,9 +261,11 @@
noexcept(noexcept(x.swap(y)));
template <class T, class Allocator, class U>
- void erase(vector<T, Allocator>& c, const U& value); // C++20
+typename vector<T, Allocator>::size_type
+erase(vector<T, Allocator>& c, const U& value); // C++20
template <class T, class Allocator, class Predicate>
- void erase_if(vector<T, Allocator>& c, Predicate pred); // C++20
+typename vector<T, Allocator>::size_type
+erase_if(vector<T, Allocator>& c, Predicate pred); // C++20
} // std
@@ -3389,14 +3391,20 @@
#if _LIBCPP_STD_VER > 17
template <class _Tp, class _Allocator, class _Up>
-inline _LIBCPP_INLINE_VISIBILITY
-void erase(vector<_Tp, _Allocator>& __c, const _Up& __v)
-{ __c.erase(_VSTD::remove(__c.begin(), __c.end(), __v), __c.end()); }
+inline _LIBCPP_INLINE_VISIBILITY typename vector<_Tp, _Allocator>::size_type
+erase(vector<_Tp, _Allocator>& __c, const _Up& __v) {
+ auto __old_size = __c.size();
+ __c.erase(_VSTD::remove(__c.begin(), __c.end(), __v), __c.end());
+ return __old_size - __c.size();
+}
template <class _Tp, class _Allocator, class _Predicate>
-inline _LIBCPP_INLINE_VISIBILITY
-void erase_if(vector<_Tp, _Allocator>& __c, _Predicate __pred)
-{ __c.erase(_VSTD::remove_if(__c.begin(), __c.end(), __pred), __c.end()); }
+inline _LIBCPP_INLINE_VISIBILITY typename vector<_Tp, _Allocator>::size_type
+erase_if(vector<_Tp, _Allocator>& __c, _Predicate __pred) {
+ auto __old_size = __c.size();
+ __c.erase(_VSTD::remove_if(__c.begin(), __c.end(), __pred), __c.end());
+ return __old_size - __c.size();
+}
#endif
_LIBCPP_END_NAMESPACE_STD