EqualTo.h

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// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "UnrealTemplate.h"
 
/**
 * Binary predicate class for performing equality comparisons.
 *
 * Uses operator== when available.
 *
 * See: https://en.cppreference.com/w/cpp/utility/functional/equal_to
 */
template <typename T = void>
struct TEqualTo
{
    constexpr auto operator()(const T& Lhs, const T& Rhs) const -> decltype(Lhs == Rhs)
    {
        return Lhs == Rhs;
    }
};
 
template <>
struct TEqualTo<void>
{
    template <typename T, typename U>
    constexpr auto operator()(T&& Lhs, U&& Rhs) const -> decltype(Forward<T>(Lhs) == Forward<U>(Rhs))
    {
        return Forward<T>(Lhs) == Forward<U>(Rhs);
    }
};