sol2/sol/functional.hpp

// The MIT License (MIT)

// Copyright (c) 2013 Danny Y., Rapptz

// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

#include "tuple.hpp"

#ifndef SOL_FUNCTIONAL_HPP
#define SOL_FUNCTIONAL_HPP

namespace sol {
namespace detail {

template<typename TFuncSignature>
struct function_traits;

template<typename T, typename R, typename... Args>
struct function_traits<R(T::*)(Args...)> {
    static const std::size_t arity = sizeof...(Args);
    static const bool is_member_function = true;
    typedef std::tuple<Args...> arg_tuple_type;
    typedef types<Args...> args_type;
    typedef R(T::* function_pointer_type)(Args...);
    typedef typename std::remove_pointer<function_pointer_type>::type function_type;
    typedef R(* free_function_pointer_type)(Args...);
    typedef R return_type;
    template<std::size_t i>
    using arg = typename std::tuple_element<i, arg_tuple_type>::type;
};

template<typename T, typename R, typename... Args>
struct function_traits<R(T::*)(Args...) const> {
    static const std::size_t arity = sizeof...(Args);
    static const bool is_member_function = true;
    typedef std::tuple<Args...> arg_tuple_type;
    typedef types<Args...> args_type;
    typedef R(T::* function_pointer_type)(Args...);
    typedef typename std::remove_pointer<function_pointer_type>::type function_type;
    typedef R(* free_function_pointer_type)(Args...);
    typedef R return_type;
    template<std::size_t i>
    using arg = typename std::tuple_element<i, arg_tuple_type>::type;
};

template<typename R, typename... Args>
struct function_traits<R(Args...)> {
    static const std::size_t arity = sizeof...(Args);
    static const bool is_member_function = false;
    typedef std::tuple<Args...> arg_tuple_type;
    typedef types<Args...> args_type;
    typedef R(function_type)(Args...);
    typedef R(*function_pointer_type)(Args...);
    typedef R(* free_function_pointer_type)(Args...);
    typedef R return_type;
    template<std::size_t i>
    using arg = typename std::tuple_element<i, arg_tuple_type>::type;
};

template<typename R, typename... Args>
struct function_traits<R(*)(Args...)> {
    static const std::size_t arity = sizeof...(Args);
    static const bool is_member_function = false;
    typedef std::tuple<Args...> arg_tuple_type;
    typedef types<Args...> args_type;
    typedef R(function_type)(Args...);
    typedef R(*function_pointer_type)(Args...);
    typedef R(* free_function_pointer_type)(Args...);
    typedef R return_type;
    template<std::size_t i>
    using arg = typename std::tuple_element<i, arg_tuple_type>::type;
};

using std::get;

template<typename Function, typename Tuple, size_t... Indices>
inline auto call(Function&& f, const Tuple& t, indices<Indices...>) -> decltype(f(get<Indices>(t)...)) {
    return f(get<Indices>(t)...);
}
} // detail

template<typename... Ret>
struct lua_return_type {
    typedef std::tuple<Ret...> type;
};

template<typename Ret>
struct lua_return_type<Ret> {
    typedef Ret type;
};

template<>
struct lua_return_type<> {
    typedef void type;
};

template<>
struct lua_return_type<void> {
    typedef void type;
};

template<typename Function, typename... Args>
inline auto call(Function&& f, const std::tuple<Args...>& t) -> decltype(detail::call(std::forward<Function>(f), t, build_indices<sizeof...(Args)>{})) {
    return call(std::forward<Function>(f), t, build_indices<sizeof...(Args)>{});
}

} // sol


#endif // SOL_FUNCTIONAL_HPP