detector.h

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/**********************************************************************
 * LeechCraft - modular cross-platform feature rich internet client.
 * Copyright (C) 2006-2014  Georg Rudoy
 *
 * Boost Software License - Version 1.0 - August 17th, 2003
 *
 * Permission is hereby granted, free of charge, to any person or organization
 * obtaining a copy of the software and accompanying documentation covered by
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 * Software, and to permit third-parties to whom the Software is furnished to
 * do so, all subject to the following:
 *
 * The copyright notices in the Software and this entire statement, including
 * the above license grant, this restriction and the following disclaimer,
 * must be included in all copies of the Software, in whole or in part, and
 * all derivative works of the Software, unless such copies or derivative
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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#pragma once
 
#include <type_traits>
 
namespace LC
{
namespace Util
{
    namespace detail
    {
        template<typename Default, typename Placeholder, template<typename...> class Op, typename... Args>
        struct IsDetected
        {
            using value_t = std::false_type;
            using type = Default;
        };
 
        template<typename Default, template<typename...> class Op, typename... Args>
        struct IsDetected<Default, std::void_t<Op<Args...>>, Op, Args...>
        {
            using value_t = std::true_type;
            using type = Op<Args...>;
        };
    }
 
    template<template<typename...> class Op, typename... Args>
    constexpr bool IsDetected_v = detail::IsDetected<void, void, Op, Args...>::value_t::value;
 
    template<typename Type, template<typename...> class Op, typename... Args>
    using IsDetected_t = typename detail::IsDetected<Type, void, Op, Args...>::type;
}
}