extension.hpp

 
#ifndef M5_UTILITY_STL_EXTENSION_HPP
#define M5_UTILITY_STL_EXTENSION_HPP
 
#include <algorithm>
#include <cstddef>
#include <type_traits>
 
namespace m5 {
namespace stl {
 
template <class C>
constexpr auto size(const C& c) -> decltype(c.size())
{
    return c.size();
}
 
template <typename T, size_t N>
constexpr auto size(const T (&)[N]) noexcept -> size_t
{
    return N;
}
 
#if __cplusplus >= 201703L
using std::clamp;
#else
template <class T>
constexpr const T& clamp(const T& v, const T& low, const T& high)
{
    return (v < low) ? low : (high < v) ? high : v;
}
 
template <class T, class Compare>
constexpr const T& clamp(const T& v, const T& low, const T& high, Compare comp)
{
    return comp(v, low) ? low : comp(high, v) ? high : v;
}
#endif
 
template <typename E>
constexpr inline typename std::underlying_type<E>::type to_underlying(const E e) noexcept
{
    return static_cast<typename std::underlying_type<E>::type>(e);
}
 
}  // namespace stl
}  // namespace m5
 
#endif