variadic_switch_return.hpp

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// Copyright (C) 2012 iwg molw5
// For conditions of distribution and use, see copyright notice in COPYING

#pragma once

#ifdef FRAMEWORK_NO_BOOST
    #error "Not implemented"
#endif

#include <utility>

#include <boost/preprocessor/config/limits.hpp>
#include <boost/preprocessor/repetition/repeat.hpp>
#include <boost/preprocessor/punctuation/comma_if.hpp>
#include <boost/preprocessor/iteration/local.hpp>

#include <framework/common/common_macros.hpp>
#include <framework/common/pack_container.hpp>

#ifndef FRAMEWORK_VARIADIC_SWITCH_LIMIT
    #define FRAMEWORK_VARIADIC_SWITCH_LIMIT 20
#else
    #if FRAMEWORK_VARIADIC_SWITCH_LIMIT > BOOST_PP_LIMIT_REPEAT
        #error "Variadic switch limit cannot exceed BOOST_PP_LIMIT_REPEAT"
    #endif
#endif

#if FRAMEWORK_VARIADIC_SWITCH_LIMIT <= 0
    #error "Invalid variadic switch limit"
#endif

namespace framework
{
    namespace detail
    {
        template <typename CaseList>
        struct variadic_switch_return_impl;
    }

    template <
        typename CaseList,
        typename Handler,
        typename Index,
        typename... Args>
    FRAMEWORK_ALWAYS_INLINE
    auto variadic_switch_return (Handler&& handler, Index&& index, Args&&... args) ->
    decltype(handler(std::forward <Args> (args)...))
    {
        return detail::variadic_switch_return_impl <CaseList>::run(
            std::forward <Handler> (handler),
            std::forward <Index> (index),
            std::forward <Args> (args)...);
    }
}

#include <framework/common/variadic_switch_return.inl>