diff options
Diffstat (limited to 'absl/types/variant.h')
| -rw-r--r-- | absl/types/variant.h | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/absl/types/variant.h b/absl/types/variant.h index 8d8b5dbd00..ebd52d28b7 100644 --- a/absl/types/variant.h +++ b/absl/types/variant.h @@ -129,7 +129,12 @@ class variant; // type (in which case, they will be swapped) or to two different types (in // which case the values will need to be moved). // -template <typename... Ts> +template < + typename... Ts, + absl::enable_if_t< + absl::conjunction<std::is_move_constructible<Ts>..., + type_traits_internal::IsSwappable<Ts>...>::value, + int> = 0> void swap(variant<Ts...>& v, variant<Ts...>& w) noexcept(noexcept(v.swap(w))) { v.swap(w); } @@ -688,12 +693,12 @@ class variant<T0, Tn...> : private variant_internal::VariantBase<T0, Tn...> { // // Swaps the values of two variant objects. // - // TODO(calabrese) - // `variant::swap()` and `swap()` rely on `std::is_(nothrow)_swappable()` - // which is introduced in C++17. So we assume `is_swappable()` is always - // true and `is_nothrow_swappable()` is same as `std::is_trivial()`. void swap(variant& rhs) noexcept( - absl::conjunction<std::is_trivial<T0>, std::is_trivial<Tn>...>::value) { + absl::conjunction< + std::is_nothrow_move_constructible<T0>, + std::is_nothrow_move_constructible<Tn>..., + type_traits_internal::IsNothrowSwappable<T0>, + type_traits_internal::IsNothrowSwappable<Tn>...>::value) { return variant_internal::VisitIndices<sizeof...(Tn) + 1>::Run( variant_internal::Swap<T0, Tn...>{this, &rhs}, rhs.index()); } |