Add is_swappable/is_nothrow_swappable traits git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@267079 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/array b/include/array index f0350ea..719286d 100644 --- a/include/array +++ b/include/array
@@ -34,7 +34,7 @@ // No explicit construct/copy/destroy for aggregate type void fill(const T& u); - void swap(array& a) noexcept(noexcept(swap(declval<T&>(), declval<T&>()))); + void swap(array& a) noexcept(is_nothrow_swappable_v<T>); // iterators: iterator begin() noexcept; @@ -141,8 +141,15 @@ _LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u) {_VSTD::fill_n(__elems_, _Size, __u);} _LIBCPP_INLINE_VISIBILITY - void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) - {_VSTD::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);} + void swap(array& __a) _NOEXCEPT_(_Size == 0 || __is_nothrow_swappable<_Tp>::value) + { __swap_dispatch((std::integral_constant<bool, _Size == 0>()), __a); } + + _LIBCPP_INLINE_VISIBILITY + void __swap_dispatch(std::true_type, array&) {} + + _LIBCPP_INLINE_VISIBILITY + void __swap_dispatch(std::false_type, array& __a) + { _VSTD::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);} // iterators: _LIBCPP_INLINE_VISIBILITY @@ -276,11 +283,12 @@ inline _LIBCPP_INLINE_VISIBILITY typename enable_if < + _Size == 0 || __is_swappable<_Tp>::value, void >::type swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y) - _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) + _NOEXCEPT_(noexcept(__x.swap(__y))) { __x.swap(__y); } 