//-----------------------------------------------------------------------------
|
// boost variant/detail/element_index.hpp header file
|
// See http://www.boost.org for updates, documentation, and revision history.
|
//-----------------------------------------------------------------------------
|
//
|
// Copyright (c) 2014-2020 Antony Polukhin
|
//
|
// 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 BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP
|
#define BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP
|
|
#include <boost/config.hpp>
|
#include <boost/variant/recursive_wrapper_fwd.hpp>
|
#include <boost/variant/variant_fwd.hpp>
|
|
#include <boost/type_traits/remove_cv.hpp>
|
#include <boost/type_traits/remove_reference.hpp>
|
#include <boost/mpl/find_if.hpp>
|
|
namespace boost { namespace detail { namespace variant {
|
|
template <class VariantElement, class T>
|
struct variant_element_functor :
|
boost::mpl::or_<
|
boost::is_same<VariantElement, T>,
|
boost::is_same<VariantElement, boost::recursive_wrapper<T> >,
|
boost::is_same<VariantElement, T& >
|
>
|
{};
|
|
template <class Types, class T>
|
struct element_iterator_impl :
|
boost::mpl::find_if<
|
Types,
|
boost::mpl::or_<
|
variant_element_functor<boost::mpl::_1, T>,
|
variant_element_functor<boost::mpl::_1, typename boost::remove_cv<T>::type >
|
>
|
>
|
{};
|
|
template <class Variant, class T>
|
struct element_iterator :
|
element_iterator_impl< typename Variant::types, typename boost::remove_reference<T>::type >
|
{};
|
|
template <class Variant, class T>
|
struct holds_element :
|
boost::mpl::not_<
|
boost::is_same<
|
typename boost::mpl::end<typename Variant::types>::type,
|
typename element_iterator<Variant, T>::type
|
>
|
>
|
{};
|
|
|
}}} // namespace boost::detail::variant
|
|
#endif // BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP
|
