/*============================================================================= | |
Copyright (c) 2001-2011 Joel de Guzman | |
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(SPIRIT_OMIT_MARCH_24_2007_0802AM) | |
#define SPIRIT_OMIT_MARCH_24_2007_0802AM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/qi/meta_compiler.hpp> | |
#include <boost/spirit/home/qi/skip_over.hpp> | |
#include <boost/spirit/home/qi/parser.hpp> | |
#include <boost/spirit/home/support/unused.hpp> | |
#include <boost/spirit/home/support/info.hpp> | |
#include <boost/spirit/home/support/common_terminals.hpp> | |
#include <boost/spirit/home/support/has_semantic_action.hpp> | |
#include <boost/spirit/home/support/handles_container.hpp> | |
namespace boost { namespace spirit | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// Enablers | |
/////////////////////////////////////////////////////////////////////////// | |
template <> | |
struct use_directive<qi::domain, tag::omit> // enables omit | |
: mpl::true_ {}; | |
}} | |
namespace boost { namespace spirit { namespace qi | |
{ | |
using spirit::omit; | |
using spirit::omit_type; | |
/////////////////////////////////////////////////////////////////////////// | |
// omit_directive forces the attribute of subject parser | |
// to be unused_type | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject> | |
struct omit_directive : unary_parser<omit_directive<Subject> > | |
{ | |
typedef Subject subject_type; | |
omit_directive(Subject const& subject) | |
: subject(subject) {} | |
template <typename Context, typename Iterator> | |
struct attribute | |
{ | |
typedef unused_type type; | |
}; | |
template <typename Iterator, typename Context | |
, typename Skipper, typename Attribute> | |
bool parse(Iterator& first, Iterator const& last | |
, Context& context, Skipper const& skipper, Attribute& attr) const | |
{ | |
return subject.parse(first, last, context, skipper, attr); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
return info("omit", subject.what(context)); | |
} | |
Subject subject; | |
private: | |
// silence MSVC warning C4512: assignment operator could not be generated | |
omit_directive& operator= (omit_directive const&); | |
}; | |
/////////////////////////////////////////////////////////////////////////// | |
// Parser generators: make_xxx function (objects) | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Modifiers> | |
struct make_directive<tag::omit, Subject, Modifiers> | |
{ | |
typedef omit_directive<Subject> result_type; | |
result_type operator()(unused_type, Subject const& subject, unused_type) const | |
{ | |
return result_type(subject); | |
} | |
}; | |
}}} | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject> | |
struct has_semantic_action<qi::omit_directive<Subject> > | |
: mpl::false_ {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Attribute, typename Context | |
, typename Iterator> | |
struct handles_container<qi::omit_directive<Subject>, Attribute | |
, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
}}} | |
#endif |