// Copyright 2019 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef V8_BASE_TYPE_TRAITS_H_ #define V8_BASE_TYPE_TRAITS_H_ #include <type_traits> namespace v8 { namespace internal { // Conjunction metafunction. template <class... Args> struct conjunction; template <> struct conjunction<> : std::true_type {}; template <class T> struct conjunction<T> : T {}; template <class T, class... Args> struct conjunction<T, Args...> : std::conditional<T::value, conjunction<Args...>, T>::type {}; // Disjunction metafunction. template <class... Args> struct disjunction; template <> struct disjunction<> : std::true_type {}; template <class T> struct disjunction<T> : T {}; template <class T, class... Args> struct disjunction<T, Args...> : std::conditional<T::value, T, disjunction<Args...>>::type {}; // Negation metafunction. template <class T> struct negation : std::integral_constant<bool, !T::value> {}; } // namespace internal } // namespace v8 #endif // V8_BASE_TYPE_TRAITS_H_