| Index: src/lazy-instance.h
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| diff --git a/src/lazy-instance.h b/src/lazy-instance.h
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| deleted file mode 100644
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| index 09dfe2154dc2992305a0b04787d8c3cca3391193..0000000000000000000000000000000000000000
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| --- a/src/lazy-instance.h
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| +++ /dev/null
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| @@ -1,216 +0,0 @@
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| -// Copyright 2012 the V8 project authors. All rights reserved.
|
| -// Redistribution and use in source and binary forms, with or without
|
| -// modification, are permitted provided that the following conditions are
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| -// met:
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| -//
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| -// * Redistributions of source code must retain the above copyright
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| -// notice, this list of conditions and the following disclaimer.
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| -// * Redistributions in binary form must reproduce the above
|
| -// copyright notice, this list of conditions and the following
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| -// disclaimer in the documentation and/or other materials provided
|
| -// with the distribution.
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| -// * Neither the name of Google Inc. nor the names of its
|
| -// contributors may be used to endorse or promote products derived
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| -// from this software without specific prior written permission.
|
| -//
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| -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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| -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
| -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
| -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
| -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
| -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
| -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
| -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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| -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
| -
|
| -// The LazyInstance<Type, Traits> class manages a single instance of Type,
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| -// which will be lazily created on the first time it's accessed. This class is
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| -// useful for places you would normally use a function-level static, but you
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| -// need to have guaranteed thread-safety. The Type constructor will only ever
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| -// be called once, even if two threads are racing to create the object. Get()
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| -// and Pointer() will always return the same, completely initialized instance.
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| -//
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| -// LazyInstance is completely thread safe, assuming that you create it safely.
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| -// The class was designed to be POD initialized, so it shouldn't require a
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| -// static constructor. It really only makes sense to declare a LazyInstance as
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| -// a global variable using the LAZY_INSTANCE_INITIALIZER initializer.
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| -//
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| -// LazyInstance is similar to Singleton, except it does not have the singleton
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| -// property. You can have multiple LazyInstance's of the same type, and each
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| -// will manage a unique instance. It also preallocates the space for Type, as
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| -// to avoid allocating the Type instance on the heap. This may help with the
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| -// performance of creating the instance, and reducing heap fragmentation. This
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| -// requires that Type be a complete type so we can determine the size. See
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| -// notes for advanced users below for more explanations.
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| -//
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| -// Example usage:
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| -// static LazyInstance<MyClass>::type my_instance = LAZY_INSTANCE_INITIALIZER;
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| -// void SomeMethod() {
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| -// my_instance.Get().SomeMethod(); // MyClass::SomeMethod()
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| -//
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| -// MyClass* ptr = my_instance.Pointer();
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| -// ptr->DoDoDo(); // MyClass::DoDoDo
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| -// }
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| -//
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| -// Additionally you can override the way your instance is constructed by
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| -// providing your own trait:
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| -// Example usage:
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| -// struct MyCreateTrait {
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| -// static void Construct(MyClass* allocated_ptr) {
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| -// new (allocated_ptr) MyClass(/* extra parameters... */);
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| -// }
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| -// };
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| -// static LazyInstance<MyClass, MyCreateTrait>::type my_instance =
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| -// LAZY_INSTANCE_INITIALIZER;
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| -//
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| -// Notes for advanced users:
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| -// LazyInstance can actually be used in two different ways:
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| -//
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| -// - "Static mode" which is the default mode since it is the most efficient
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| -// (no extra heap allocation). In this mode, the instance is statically
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| -// allocated (stored in the global data section at compile time).
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| -// The macro LAZY_STATIC_INSTANCE_INITIALIZER (= LAZY_INSTANCE_INITIALIZER)
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| -// must be used to initialize static lazy instances.
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| -//
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| -// - "Dynamic mode". In this mode, the instance is dynamically allocated and
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| -// constructed (using new) by default. This mode is useful if you have to
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| -// deal with some code already allocating the instance for you (e.g.
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| -// OS::Mutex() which returns a new private OS-dependent subclass of Mutex).
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| -// The macro LAZY_DYNAMIC_INSTANCE_INITIALIZER must be used to initialize
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| -// dynamic lazy instances.
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| -
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| -#ifndef V8_LAZY_INSTANCE_H_
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| -#define V8_LAZY_INSTANCE_H_
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| -
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| -#include "once.h"
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| -
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| -namespace v8 {
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| -namespace internal {
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| -
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| -#define LAZY_STATIC_INSTANCE_INITIALIZER { V8_ONCE_INIT, {} }
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| -#define LAZY_DYNAMIC_INSTANCE_INITIALIZER { V8_ONCE_INIT, 0 }
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| -
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| -// Default to static mode.
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| -#define LAZY_INSTANCE_INITIALIZER LAZY_STATIC_INSTANCE_INITIALIZER
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| -
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| -
|
| -template <typename T>
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| -struct LeakyInstanceTrait {
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| - static void Destroy(T* /* instance */) {}
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| -};
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| -
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| -
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| -// Traits that define how an instance is allocated and accessed.
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| -
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| -template <typename T>
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| -struct StaticallyAllocatedInstanceTrait {
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| - typedef char StorageType[sizeof(T)];
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| -
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| - static T* MutableInstance(StorageType* storage) {
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| - return reinterpret_cast<T*>(storage);
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| - }
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| -
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| - template <typename ConstructTrait>
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| - static void InitStorageUsingTrait(StorageType* storage) {
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| - ConstructTrait::Construct(MutableInstance(storage));
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| - }
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| -};
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| -
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| -
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| -template <typename T>
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| -struct DynamicallyAllocatedInstanceTrait {
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| - typedef T* StorageType;
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| -
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| - static T* MutableInstance(StorageType* storage) {
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| - return *storage;
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| - }
|
| -
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| - template <typename CreateTrait>
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| - static void InitStorageUsingTrait(StorageType* storage) {
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| - *storage = CreateTrait::Create();
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| - }
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| -};
|
| -
|
| -
|
| -template <typename T>
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| -struct DefaultConstructTrait {
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| - // Constructs the provided object which was already allocated.
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| - static void Construct(T* allocated_ptr) {
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| - new(allocated_ptr) T();
|
| - }
|
| -};
|
| -
|
| -
|
| -template <typename T>
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| -struct DefaultCreateTrait {
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| - static T* Create() {
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| - return new T();
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| - }
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| -};
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| -
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| -
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| -// TODO(pliard): Handle instances destruction (using global destructors).
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| -template <typename T, typename AllocationTrait, typename CreateTrait,
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| - typename DestroyTrait /* not used yet. */ >
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| -struct LazyInstanceImpl {
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| - public:
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| - typedef typename AllocationTrait::StorageType StorageType;
|
| -
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| - private:
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| - static void InitInstance(StorageType* storage) {
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| - AllocationTrait::template InitStorageUsingTrait<CreateTrait>(storage);
|
| - }
|
| -
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| - void Init() const {
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| - CallOnce(&once_, &InitInstance, &storage_);
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| - }
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| -
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| - public:
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| - T* Pointer() {
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| - Init();
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| - return AllocationTrait::MutableInstance(&storage_);
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| - }
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| -
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| - const T& Get() const {
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| - Init();
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| - return *AllocationTrait::MutableInstance(&storage_);
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| - }
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| -
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| - mutable OnceType once_;
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| - // Note that the previous field, OnceType, is an AtomicWord which guarantees
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| - // the correct alignment of the storage field below.
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| - mutable StorageType storage_;
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| -};
|
| -
|
| -
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| -template <typename T,
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| - typename CreateTrait = DefaultConstructTrait<T>,
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| - typename DestroyTrait = LeakyInstanceTrait<T> >
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| -struct LazyStaticInstance {
|
| - typedef LazyInstanceImpl<T, StaticallyAllocatedInstanceTrait<T>, CreateTrait,
|
| - DestroyTrait> type;
|
| -};
|
| -
|
| -
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| -template <typename T,
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| - typename CreateTrait = DefaultConstructTrait<T>,
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| - typename DestroyTrait = LeakyInstanceTrait<T> >
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| -struct LazyInstance {
|
| - // A LazyInstance is a LazyStaticInstance.
|
| - typedef typename LazyStaticInstance<T, CreateTrait, DestroyTrait>::type type;
|
| -};
|
| -
|
| -
|
| -template <typename T,
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| - typename CreateTrait = DefaultConstructTrait<T>,
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| - typename DestroyTrait = LeakyInstanceTrait<T> >
|
| -struct LazyDynamicInstance {
|
| - typedef LazyInstanceImpl<T, DynamicallyAllocatedInstanceTrait<T>, CreateTrait,
|
| - DestroyTrait> type;
|
| -};
|
| -
|
| -} } // namespace v8::internal
|
| -
|
| -#endif // V8_LAZY_INSTANCE_H_
|
|
|