vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/metaparse/v1/keyword.hpp

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2.3 KiB
C++

#ifndef BOOST_METAPARSE_V1_KEYWORD_HPP
#define BOOST_METAPARSE_V1_KEYWORD_HPP
// Copyright Abel Sinkovics (abel@sinkovics.hu) 2009 - 2010.
// 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)
#include <boost/metaparse/v1/impl/void_.hpp>
#include <boost/metaparse/v1/lit.hpp>
#include <boost/metaparse/v1/return_.hpp>
#include <boost/metaparse/v1/is_error.hpp>
#include <boost/metaparse/v1/get_remaining.hpp>
#include <boost/metaparse/v1/get_position.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/empty.hpp>
#include <boost/mpl/pop_front.hpp>
#include <boost/mpl/front.hpp>
namespace boost
{
namespace metaparse
{
namespace v1
{
// Does not consume/check anything after the keyword
template <class Kw, class ResultType = impl::void_>
struct keyword
{
private:
struct nonempty
{
private:
typedef lit<typename boost::mpl::front<Kw>::type> next_char_parser;
typedef
keyword<typename boost::mpl::pop_front<Kw>::type, ResultType>
rest_parser;
template <class S, class Pos>
struct apply_unchecked :
rest_parser::template apply<
typename get_remaining<
typename next_char_parser::template apply<S, Pos>
>::type,
typename get_position<
typename next_char_parser::template apply<S, Pos>
>::type
>
{};
public:
template <class S, class Pos>
struct apply :
boost::mpl::eval_if<
typename is_error<
typename next_char_parser::template apply<S, Pos>
>::type,
typename next_char_parser::template apply<S, Pos>,
apply_unchecked<S, Pos>
>
{};
};
public:
typedef keyword type;
template <class S, class Pos>
struct apply :
boost::mpl::if_<
boost::mpl::empty<Kw>,
return_<ResultType>,
nonempty
>::type::template apply<S, Pos>
{};
};
}
}
}
#endif