References.h

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// Copyright Epic Games, Inc. All Rights Reserved.
// Templates for handling different types of references
 
#pragma once
 
#include "uLang/Common/Templates/TypeTraits.h"
 
namespace uLang
{
 
//------------------------------------------------------------------
// From RemoveReference.h
 
template <typename T> struct TRemoveReference      { using Type = T; };
template <typename T> struct TRemoveReference<T& > { using Type = T; };
template <typename T> struct TRemoveReference<T&&> { using Type = T; };
 
//------------------------------------------------------------------
// From Decay.h
 
namespace Private
{
    template <typename T>
    struct TDecayNonReference
    {
        using Type = typename TRemoveCV<T>::Type;
    };
 
    template <typename T>
    struct TDecayNonReference<T[]>
    {
        using Type = T*;
    };
 
    template <typename T, uint32_t N>
    struct TDecayNonReference<T[N]>
    {
        using Type = T*;
    };
 
    template <typename RetType, typename... Params>
    struct TDecayNonReference<RetType(Params...)>
    {
        using Type = RetType (*)(Params...);
    };
}
 
template <typename T>
struct TDecay
{
    using Type = typename Private::TDecayNonReference<typename TRemoveReference<T>::Type>::Type;
};
 
template <typename T>
using TDecayT = typename TDecay<T>::Type;
 
//------------------------------------------------------------------
// From UnrealTemplate.h
 
template <typename T> struct TRemovePointer { typedef T Type; };
template <typename T> struct TRemovePointer<T*> { typedef T Type; };
 
template <typename T>
ULANG_FORCEINLINE typename TRemoveReference<T>::Type&& Move(T&& Obj)
{
    using CastType = typename TRemoveReference<T>::Type;
 
    // Validate that we're not being passed an rvalue or a const object - the former is redundant, the latter is almost certainly a mistake
    static_assert(TIsLValueReferenceType<T>::Value, "Move called on an rvalue");
    static_assert(!TAreTypesEqual<CastType&, const CastType&>::Value, "Move called on a const object");
 
    return (CastType&&)Obj;
}
 
template <typename T>
ULANG_FORCEINLINE typename TRemoveReference<T>::Type&& MoveIfPossible(T&& Obj)
{
    using CastType = typename TRemoveReference<T>::Type;
    return (CastType&&)Obj;
}
 
template <typename T>
ULANG_FORCEINLINE T&& ForwardArg(typename TRemoveReference<T>::Type& Obj)
{
    return (T&&)Obj;
}
 
template <typename T>
ULANG_FORCEINLINE T&& ForwardArg(typename TRemoveReference<T>::Type&& Obj)
{
    return (T&&)Obj;
}
 
}