标准库头文件 <scoped_allocator>

< cpp‎ | header
 
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<scoped_allocator>    
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C 兼容
 

此头文件是动态内存管理库的一部分。

类

(C++11)
 为多级容器实现的多级分配器
(类模板)

函数

(C++20 中移除)
 比较两个 scoped_allocator_adaptor 实例
(std::scoped_allocator_adaptor<OuterAlloc,InnerAlloc...> 的公开成员函数)

概要

namespace std {
  // 类模板 scoped_allocator_adaptor
  template<class OuterAlloc, class... InnerAlloc>
    class scoped_allocator_adaptor;
 
  // 有作用域分配器运算符
  template<class OuterA1, class OuterA2, class... InnerAllocs>
    bool operator==(const scoped_allocator_adaptor<OuterA1, InnerAllocs...>& a,
                    const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& b) noexcept;
}

类模板 std::scoped_allocator_adaptor

namespace std {
  template<class OuterAlloc, class... InnerAllocs>
  class scoped_allocator_adaptor : public OuterAlloc {
  private:
    using OuterTraits = allocator_traits<OuterAlloc>;   // 仅用于阐释
    scoped_allocator_adaptor<InnerAllocs...> inner;     // 仅用于阐释
 
  public:
    using outer_allocator_type = OuterAlloc;
    using inner_allocator_type = /* 见描述 */;
 
    using value_type           = typename OuterTraits::value_type;
    using size_type            = typename OuterTraits::size_type;
    using difference_type      = typename OuterTraits::difference_type;
    using pointer              = typename OuterTraits::pointer;
    using const_pointer        = typename OuterTraits::const_pointer;
    using void_pointer         = typename OuterTraits::void_pointer;
    using const_void_pointer   = typename OuterTraits::const_void_pointer;
 
    using propagate_on_container_copy_assignment = /* 见描述 */;
    using propagate_on_container_move_assignment = /* 见描述 */;
    using propagate_on_container_swap            = /* 见描述 */;
    using is_always_equal                        = /* 见描述 */;
 
    template<class Tp> struct rebind {
      using other = scoped_allocator_adaptor<
        OuterTraits::template rebind_alloc<Tp>, InnerAllocs...>;
    };
 
    scoped_allocator_adaptor();
    template<class OuterA2>
      scoped_allocator_adaptor(OuterA2&& outerAlloc,
                               const InnerAllocs&... innerAllocs) noexcept;
 
    scoped_allocator_adaptor(const scoped_allocator_adaptor& other) noexcept;
    scoped_allocator_adaptor(scoped_allocator_adaptor&& other) noexcept;
 
    template<class OuterA2>
      scoped_allocator_adaptor(
        const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& other) noexcept;
    template<class OuterA2>
      scoped_allocator_adaptor(
        scoped_allocator_adaptor<OuterA2, InnerAllocs...>&& other) noexcept;
 
    scoped_allocator_adaptor& operator=(const scoped_allocator_adaptor&) = default;
    scoped_allocator_adaptor& operator=(scoped_allocator_adaptor&&) = default;
 
    ~scoped_allocator_adaptor();
 
    inner_allocator_type& inner_allocator() noexcept;
    const inner_allocator_type& inner_allocator() const noexcept;
    outer_allocator_type& outer_allocator() noexcept;
    const outer_allocator_type& outer_allocator() const noexcept;
 
    [[nodiscard]] pointer allocate(size_type n);
    [[nodiscard]] pointer allocate(size_type n, const_void_pointer hint);
    void deallocate(pointer p, size_type n);
    size_type max_size() const;
 
    template<class T, class... Args>
      void construct(T* p, Args&&... args);
 
    template<class T>
      void destroy(T* p);
 
    scoped_allocator_adaptor select_on_container_copy_construction() const;
  };
 
  template<class OuterAlloc, class... InnerAllocs>
    scoped_allocator_adaptor(OuterAlloc, InnerAllocs...)
      -> scoped_allocator_adaptor<OuterAlloc, InnerAllocs...>;
}