EnumAsByte.h

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// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "CoreTypes.h"
#include "Templates/IsPODType.h"
#include "Templates/TypeHash.h"
 
template <class InEnumType>
class TEnumAsByte
{
    static_assert(std::is_enum_v<InEnumType> && std::is_convertible_v<InEnumType, int>, "TEnumAsByte is not intended for use with enum classes - please derive your enum class from uint8 instead.");
 
public:
    using EnumType = InEnumType;
 
    [[nodiscard]] constexpr TEnumAsByte() = default;
    [[nodiscard]] constexpr TEnumAsByte(const TEnumAsByte&) = default;
    constexpr TEnumAsByte& operator=(const TEnumAsByte&) = default;
 
    [[nodiscard]] UE_FORCEINLINE_HINT constexpr TEnumAsByte( EnumType InValue )
        : Value(static_cast<uint8>(InValue))
    {
    }
 
    [[nodiscard]] explicit UE_FORCEINLINE_HINT constexpr TEnumAsByte( int32 InValue )
        : Value(static_cast<uint8>(InValue))
    {
    }
 
    [[nodiscard]] explicit UE_FORCEINLINE_HINT constexpr TEnumAsByte( uint8 InValue )
        : Value(InValue)
    {
    }
 
public:
    [[nodiscard]] constexpr bool operator==( EnumType InValue ) const
    {
        return static_cast<EnumType>(Value) == InValue;
    }
 
    [[nodiscard]] constexpr bool operator==(TEnumAsByte InValue) const
    {
        return Value == InValue.Value;
    }
 
    [[nodiscard]] constexpr operator EnumType() const
    {
        return (EnumType)Value;
    }
 
public:
 
    [[nodiscard]] constexpr EnumType GetValue() const
    {
        return (EnumType)Value;
    }
 
    [[nodiscard]] constexpr uint8 GetIntValue() const
    {
        return Value;
    }
 
private:
 
    uint8 Value;
};
 
template<class T>
[[nodiscard]] UE_FORCEINLINE_HINT constexpr uint32 GetTypeHash(const TEnumAsByte<T>& Enum)
{
    return GetTypeHash((uint8)Enum.GetValue());
}
 
 
template<class T> struct TIsPODType<TEnumAsByte<T>> { enum { Value = true }; };
 
#if UE_ENABLE_INCLUDE_ORDER_DEPRECATED_IN_5_6
#include "Traits/IsTEnumAsByte.h"
#endif