| // Copyright (c) 2018 The Chromium 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 HeapTraits_h |
| #define HeapTraits_h |
| |
| #include <type_traits> |
| #include "platform/heap/HeapAllocator.h" |
| #include "platform/heap/Member.h" |
| #include "platform/wtf/TypeTraits.h" |
| |
| namespace blink { |
| |
| // Given a type T, returns a type that is either Member<T> or just T depending |
| // on whether T is a garbage-collected type. |
| template <typename T> |
| using AddMemberIfNeeded = |
| std::conditional_t<WTF::IsGarbageCollectedType<T>::value, Member<T>, T>; |
| |
| // Given a type T, returns a type that is either HeapVector<T>, |
| // HeapVector<Member<T>> or Vector<T> depending on T. |
| template <typename T> |
| using VectorOf = std::conditional_t<WTF::IsTraceable<T>::value, |
| HeapVector<AddMemberIfNeeded<T>>, |
| Vector<T>>; |
| |
| // Given types T and U, returns a type that is one of the following: |
| // - HeapVector<std::pair<V, X>> |
| // (where V is either T or Member<T> and X is either U or Member<U>) |
| // - Vector<std::pair<T, U>> |
| template <typename T, typename U> |
| using VectorOfPairs = std::conditional_t< |
| WTF::IsTraceable<T>::value || WTF::IsTraceable<U>::value, |
| HeapVector<std::pair<AddMemberIfNeeded<T>, AddMemberIfNeeded<U>>>, |
| Vector<std::pair<T, U>>>; |
| |
| } // namespace blink |
| |
| #endif // HeapTraits_h |
