Implement n3668 - std::exchange git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185863 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/utility b/include/utility index ba65649..a2cafbf 100644 --- a/include/utility +++ b/include/utility
@@ -138,6 +138,8 @@ template<class... T> using index_sequence_for = make_index_sequence<sizeof...(T)>; +template<class T, class U=T> + T exchange(T& obj, U&& new_value); } // std */ @@ -685,6 +687,17 @@ #endif // _LIBCPP_STD_VER > 11 +#if _LIBCPP_STD_VER > 11 +template<class _T1, class _T2 = _T1> +_LIBCPP_INLINE_VISIBILITY inline +_T1 exchange(_T1& __obj, _T2 && __new_value) +{ + _T1 __old_value = _VSTD::move(__obj); + __obj = _VSTD::forward<_T2>(__new_value); + return __old_value; +} +#endif // _LIBCPP_STD_VER > 11 + _LIBCPP_END_NAMESPACE_STD #endif // _LIBCPP_UTILITY 