# 实验性库头文件 <experimental/ranges/type_traits>

< cpp‎ | header‎ | experimental

此头文件是范围的一部分。

### 元编程与类型特征

定义于命名空间 `std::experimental::ranges`
is_swappable_with is_swappable is_nothrow_swappable_with is_nothrow_swappable | 检查一个类型的对象是否能与相同或不同类型的对象交换 (类模板)
common_reference | 确定类型集合的公共引用类型 (类模板)
common_type | 确定类型集合的公共类型 (类模板)

### 概要

    namespace std { namespace experimental { namespace ranges { inline namespace v1 {

    template <class T, class U> struct is_swappable_with;
    template <class T> struct is_swappable;

    template <class T, class U> struct is_nothrow_swappable_with;
    template <class T> struct is_nothrow_swappable;

    template <class T, class U> constexpr bool is_swappable_with_v
      = is_swappable_with<T, U>::value;
    template <class T> constexpr bool is_swappable_v
      = is_swappable<T>::value;

    template <class T, class U> constexpr bool is_nothrow_swappable_with_v
      = is_nothrow_swappable_with<T, U>::value;
    template <class T> constexpr bool is_nothrow_swappable_v
      = is_nothrow_swappable<T>::value;

    template <class... T> struct common_type;
    template <class T, class U, template <class> class TQual, template <class> class UQual>
      struct basic_common_reference { };
    template <class... T> struct common_reference;

    template <class... T>
      using common_type_t = typename common_type<T...>::type;
    template <class... T>
      using common_reference_t = typename common_reference<T...>::type;

    }}}}