标准库头文件 <scoped_allocator>

 

C++

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标准库头文件

自立与有宿主实现

具名要求

语言支持库

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诊断库

工具库

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输入/输出库

文件系统库 (C++17)

正则表达式库 (C++11)

原子操作库 (C++11)

线程支持库 (C++11)

技术规范

 

标准库头文件

语言支持
<cstddef> <cstdlib> <version> <limits> <climits>	<cfloat> <cstdint> <new> <typeinfo>	<source_location> <exception> <initializer_list>     <compare>	<coroutine> <csignal> <csetjmp> <cstdarg>
概念
<concepts>
诊断
<stdexcept>	<cassert>	<cerrno>	<system_error>
通用工具
<utility> <memory> <memory_resource> <scoped_allocator>	<bitset> <tuple> <optional> <any>	<variant> <type_traits> <ratio> <chrono>	<typeindex> <functional> <stacktrace> <ctime>
字符串
<string> <string_view> <cstring>	<charconv> <format>	<cctype> <cwctype>	<cwchar> <cuchar>
本地化
<locale>	<codecvt>	<clocale>
容器
<span> <array> <vector>	<deque> <forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
迭代器
<iterator>
范围
<ranges>
算法
<algorithm>	<execution>
数值
<complex> <random>	<valarray> <numeric>	<bit> <numbers>	<cfenv> <cmath>
输入/输出
<iosfwd> <ios> <iomanip> <streambuf>	<istream> <ostream> <iostream>	<sstream> <spanstream> <fstream> <syncstream>	<cstdio> <cinttypes> <strstream>
正则表达式
<regex>
文件系统
<filesystem>
线程支持
<thread> <atomic> <mutex>	<shared_mutex> <condition_variable>     <future>	<stop_token> <semaphore>	<latch> <barrier>
C 兼容
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath> <stdatomic.h>

 

此头文件是动态内存管理库的一部分。

类
scoped_allocator_adaptor (C++11)	为多级容器实现的多级分配器 (类模板)
函数
operator==operator!= (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...>;
}