vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/spirit/home/lex/argument.hpp

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// Copyright (c) 2001-2011 Hartmut Kaiser
// Copyright (c) 2001-2011 Joel de Guzman
// Copyright (c) 2010 Bryce Lelbach
// Copyright (c) 2011 Thomas Heller
//
// 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)
#if !defined(BOOST_SPIRIT_LEX_ARGUMENT_JUNE_07_2009_1106AM)
#define BOOST_SPIRIT_LEX_ARGUMENT_JUNE_07_2009_1106AM
#if defined(_MSC_VER)
#pragma once
#endif
#include <boost/spirit/include/phoenix_core.hpp>
#include <boost/spirit/include/phoenix_operator.hpp>
#include <boost/spirit/home/support/string_traits.hpp>
#include <boost/spirit/home/lex/argument_phoenix.hpp>
#include <boost/fusion/include/at.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/type_traits/remove_reference.hpp>
///////////////////////////////////////////////////////////////////////////////
namespace boost { namespace spirit { namespace lex
{
///////////////////////////////////////////////////////////////////////////
// The state_getter is a Phoenix actor used to access the name of the
// current lexer state by calling get_state_name() on the context (which
// is the 5th parameter to any lexer semantic actions).
//
// This Phoenix actor is invoked whenever the placeholder '_state' is used
// as a rvalue inside a lexer semantic action:
//
// lex::token_def<> identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
// this->self = identifier [ std::cout << _state ];
//
// The example shows how to print the lexer state after matching a token
// 'identifier'.
struct state_getter
{
typedef mpl::true_ no_nullary;
template <typename Env>
struct result
{
typedef
typename remove_reference<
typename remove_const<
typename mpl::at_c<typename Env::args_type, 4>::type
>::type
>::type
context_type;
typedef typename context_type::state_name_type type;
};
template <typename Env>
typename result<Env>::type
eval(Env const& env) const
{
return fusion::at_c<4>(env.args()).get_state_name();
}
};
///////////////////////////////////////////////////////////////////////////
// The state_setter is a Phoenix actor used to change the name of the
// current lexer state by calling set_state_name() on the context (which
// is the 5th parameter to any lexer semantic actions).
//
// This Phoenix actor is invoked whenever the placeholder '_state' is used
// as a lvalue inside a lexer semantic action:
//
// lex::token_def<> identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
// this->self = identifier [ _state = "SOME_LEXER_STATE" ];
//
// The example shows how to change the lexer state after matching a token
// 'identifier'.
template <typename Actor>
struct state_setter
{
typedef mpl::true_ no_nullary;
template <typename Env>
struct result
{
typedef void type;
};
template <typename Env>
void eval(Env const& env) const
{
fusion::at_c<4>(env.args()).set_state_name(
traits::get_c_string(actor_.eval(env)));
}
state_setter(Actor const& actor)
: actor_(actor) {}
Actor actor_;
};
///////////////////////////////////////////////////////////////////////////
// The value_getter is used to create the _val placeholder, which is a
// Phoenix actor used to access the value of the current token.
//
// This Phoenix actor is invoked whenever the placeholder '_val' is used
// as a rvalue inside a lexer semantic action:
//
// lex::token_def<> identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
// this->self = identifier [ std::cout << _val ];
//
// The example shows how to use _val to print the identifier name (which
// is the initial token value).
struct value_getter
{
typedef mpl::true_ no_nullary;
template <typename Env>
struct result
{
typedef
typename remove_reference<
typename remove_const<
typename mpl::at_c<typename Env::args_type, 4>::type
>::type
>::type
context_type;
typedef typename context_type::get_value_type type;
};
template <typename Env>
typename result<Env>::type
eval(Env const& env) const
{
return fusion::at_c<4>(env.args()).get_value();
}
};
///////////////////////////////////////////////////////////////////////////
// The value_setter is a Phoenix actor used to change the name of the
// current lexer state by calling set_state_name() on the context (which
// is the 5th parameter to any lexer semantic actions).
//
// This Phoenix actor is invoked whenever the placeholder '_val' is used
// as a lvalue inside a lexer semantic action:
//
// lex::token_def<> identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
// this->self = identifier [ _val = "identifier" ];
//
// The example shows how to change the token value after matching a token
// 'identifier'.
template <typename Actor>
struct value_setter
{
typedef mpl::true_ no_nullary;
template <typename Env>
struct result
{
typedef void type;
};
template <typename Env>
void eval(Env const& env) const
{
fusion::at_c<4>(env.args()).set_value(actor_.eval(env));
}
value_setter(Actor const& actor)
: actor_(actor) {}
Actor actor_;
};
///////////////////////////////////////////////////////////////////////////
// The eoi_getter is used to create the _eoi placeholder, which is a
// Phoenix actor used to access the end of input iterator pointing to the
// end of the underlying input sequence.
//
// This actor is invoked whenever the placeholder '_eoi' is used in a
// lexer semantic action:
//
// lex::token_def<> identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
// this->self = identifier
// [ std::cout << construct_<std::string>(_end, _eoi) ];
//
// The example shows how to use _eoi to print all remaining input after
// matching a token 'identifier'.
struct eoi_getter
{
typedef mpl::true_ no_nullary;
template <typename Env>
struct result
{
typedef
typename remove_reference<
typename remove_const<
typename mpl::at_c<typename Env::args_type, 4>::type
>::type
>::type
context_type;
typedef typename context_type::base_iterator_type const& type;
};
template <typename Env>
typename result<Env>::type
eval(Env const& env) const
{
return fusion::at_c<4>(env.args()).get_eoi();
}
};
///////////////////////////////////////////////////////////////////////////
// '_start' and '_end' may be used to access the start and the end of
// the matched sequence of the current token
typedef phoenix::arg_names::_1_type _start_type;
typedef phoenix::arg_names::_2_type _end_type;
#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
_start_type const _start = _start_type();
_end_type const _end = _end_type();
#endif
// We are reusing the placeholder '_pass' to access and change the pass
// status of the current match (see support/argument.hpp for its
// definition).
// typedef phoenix::arg_names::_3_type _pass_type;
using boost::spirit::_pass_type;
#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
using boost::spirit::_pass;
#endif
// '_tokenid' may be used to access and change the tokenid of the current
// token
typedef phoenix::arg_names::_4_type _tokenid_type;
#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
_tokenid_type const _tokenid = _tokenid_type();
#endif
typedef phoenix::actor<value_context> _val_type;
typedef phoenix::actor<state_context> _state_type;
typedef phoenix::actor<eoi_getter> _eoi_type;
#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
// '_val' may be used to access and change the token value of the current
// token
_val_type const _val = _val_type();
// _state may be used to access and change the name of the current lexer
// state
_state_type const _state = _state_type();
// '_eoi' may be used to access the end of input iterator of the input
// stream used by the lexer to match tokens from
_eoi_type const _eoi = _eoi_type();
#endif
}}}
#undef SPIRIT_DECLARE_ARG
#endif