enum.hpp

#ifndef ENTT_CORE_ENUM_HPP
#define ENTT_CORE_ENUM_HPP
 
#include <type_traits>
 
namespace entt {
 
template<typename Type, typename = void>
struct enum_as_bitmask: std::false_type {};
 
template<typename Type>
struct enum_as_bitmask<Type, std::void_t<decltype(Type::_entt_enum_as_bitmask)>>: std::is_enum<Type> {};
 
template<typename Type>
inline constexpr bool enum_as_bitmask_v = enum_as_bitmask<Type>::value;
 
} // namespace entt
 
template<typename Type>
[[nodiscard]] constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type>
operator|(const Type lhs, const Type rhs) noexcept {
    return static_cast<Type>(static_cast<std::underlying_type_t<Type>>(lhs) | static_cast<std::underlying_type_t<Type>>(rhs));
}
 
template<typename Type>
[[nodiscard]] constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type>
operator&(const Type lhs, const Type rhs) noexcept {
    return static_cast<Type>(static_cast<std::underlying_type_t<Type>>(lhs) & static_cast<std::underlying_type_t<Type>>(rhs));
}
 
template<typename Type>
[[nodiscard]] constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type>
operator^(const Type lhs, const Type rhs) noexcept {
    return static_cast<Type>(static_cast<std::underlying_type_t<Type>>(lhs) ^ static_cast<std::underlying_type_t<Type>>(rhs));
}
 
template<typename Type>
[[nodiscard]] constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type>
operator~(const Type value) noexcept {
    return static_cast<Type>(~static_cast<std::underlying_type_t<Type>>(value));
}
 
template<typename Type>
[[nodiscard]] constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, bool>
operator!(const Type value) noexcept {
    return !static_cast<std::underlying_type_t<Type>>(value);
}
 
template<typename Type>
constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type &>
operator|=(Type &lhs, const Type rhs) noexcept {
    return (lhs = (lhs | rhs));
}
 
template<typename Type>
constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type &>
operator&=(Type &lhs, const Type rhs) noexcept {
    return (lhs = (lhs & rhs));
}
 
template<typename Type>
constexpr std::enable_if_t<entt::enum_as_bitmask_v<Type>, Type &>
operator^=(Type &lhs, const Type rhs) noexcept {
    return (lhs = (lhs ^ rhs));
}
 
#endif