type_traits.h

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/*
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*/
 
#ifndef MYSQL_HARNESS_STDX_TYPE_TRAITS_H_
#define MYSQL_HARNESS_STDX_TYPE_TRAITS_H_
 
#include <type_traits>
 
namespace stdx {
 
// from http://wg21.link/P0463 (part of C++20)
enum class endian {
#ifdef _WIN32
  little = 0,
  big = 1,
  native = little
#else
  little = __ORDER_LITTLE_ENDIAN__,
  big = __ORDER_BIG_ENDIAN__,
  native = __BYTE_ORDER__,
#endif
};
 
// from C++23
// wg21.link/P1048
 
// all non-enums are also non-scoped-enums
template <class T, bool B = std::is_enum_v<T>>
struct __is_scoped_enum_helper : std::false_type {};
 
// scoped enums are enum's that can't be automatically be converted into its
// underlying type.
template <class T>
struct __is_scoped_enum_helper<T, true>
    : std::bool_constant<!std::is_convertible_v<T, std::underlying_type_t<T>>> {
};
 
template <class T>
struct is_scoped_enum : __is_scoped_enum_helper<T> {};
 
template <class E>
inline constexpr bool is_scoped_enum_v = is_scoped_enum<E>::value;
 
// C++20
template <class T>
struct remove_cvref {
  using type = std::remove_cv_t<std::remove_reference_t<T>>;
};
 
template <class T>
using remove_cvref_t = typename remove_cvref<T>::type;
 
template <class T>
struct type_identity {
  using type = T;
};
 
template <class T>
using type_identity_t = typename type_identity<T>::type;
 
}  // namespace stdx
 
#endif