Sprout/sprout/generator/next_generator.hpp
2014-02-22 16:32:51 +09:00

100 lines
4.2 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#ifndef SPROUT_GENERATOR_NEXT_GENERATOR_HPP
#define SPROUT_GENERATOR_NEXT_GENERATOR_HPP
#include <utility>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
#include <sprout/generator/generator_access_traits.hpp>
#include <sprout/adl/not_found.hpp>
namespace sprout_adl {
sprout::not_found_via_adl get_next_generator(...);
} // namespace sprout_adl
namespace sprout_generator_detail {
using sprout_adl::get_next_generator;
template<typename Gen>
inline SPROUT_CONSTEXPR decltype(sprout::generators::generator_access_traits<Gen>::get_next_generator(std::declval<Gen&>()))
get_next_generator(Gen& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout::generators::generator_access_traits<Gen>::get_next_generator(std::declval<Gen&>())))
{
return sprout::generators::generator_access_traits<Gen>::get_next_generator(gen);
}
template<typename Gen>
inline SPROUT_CONSTEXPR typename std::enable_if<
!std::is_const<Gen>::value && !std::is_volatile<Gen>::value && !std::is_reference<Gen>::value,
decltype(sprout::generators::generator_access_traits<typename std::remove_reference<Gen>::type>::get_next_generator(std::declval<Gen&&>()))
>::type
get_next_generator(Gen&& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout::generators::generator_access_traits<typename std::remove_reference<Gen>::type>::get_next_generator(std::declval<Gen&&>())))
{
return sprout::generators::generator_access_traits<Gen>::get_next_generator(gen);
}
template<typename Gen>
inline SPROUT_CONSTEXPR decltype(sprout::generators::generator_access_traits<Gen const>::get_next_generator(std::declval<Gen const&>()))
get_next_generator(Gen const& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout::generators::generator_access_traits<Gen const>::get_next_generator(std::declval<Gen const&>())))
{
return sprout::generators::generator_access_traits<Gen const>::get_next_generator(gen);
}
template<typename Gen>
inline SPROUT_CONSTEXPR decltype(get_next_generator(std::declval<Gen&>()))
call_get_next_generator(Gen& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(get_next_generator(std::declval<Gen&>())))
{
return get_next_generator(gen);
}
template<typename Gen>
inline SPROUT_CONSTEXPR typename std::enable_if<
!std::is_const<Gen>::value && !std::is_volatile<Gen>::value && !std::is_reference<Gen>::value,
decltype(get_next_generator(std::declval<Gen&&>()))
>::type
call_get_next_generator(Gen&& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(get_next_generator(std::declval<Gen&&>())))
{
return get_next_generator(gen);
}
template<typename Gen>
inline SPROUT_CONSTEXPR decltype(get_next_generator(std::declval<Gen const&>()))
call_get_next_generator(Gen const& gen)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(get_next_generator(std::declval<Gen const&>())))
{
return get_next_generator(gen);
}
} // namespace sprout_generator_detail
namespace sprout {
namespace generators {
//
// next_generator
//
// effect:
// ADL callable get_next_generator(t) -> get_next_generator(t)
// otherwise -> sprout::generators::generator_access_traits<T>::get_next_generator(t)
// [default]
// member callable t.next_generator() -> t.next_generator()
// otherwise -> sprout::tuples::get<0>(t)
//
template<typename T>
inline SPROUT_CONSTEXPR decltype(sprout_generator_detail::call_get_next_generator(std::declval<T>()))
next_generator(T&& t)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout_generator_detail::call_get_next_generator(std::declval<T>())))
{
return sprout_generator_detail::call_get_next_generator(SPROUT_FORWARD(T, t));
}
} // namespace generators
using sprout::generators::next_generator;
} // namespace sprout
#endif // #ifndef SPROUT_GENERATOR_NEXT_GENERATOR_HPP