// Copyright (c) 2001-2011 Joel de Guzman | |
// Copyright (c) 2001-2011 Hartmut Kaiser | |
// | |
// 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_KARMA_REFERENCE_APR_17_2009_1057PM) | |
#define BOOST_SPIRIT_KARMA_REFERENCE_APR_17_2009_1057PM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/karma/meta_compiler.hpp> | |
#include <boost/spirit/home/karma/generator.hpp> | |
#include <boost/spirit/home/support/info.hpp> | |
#include <boost/spirit/home/support/handles_container.hpp> | |
#include <boost/type_traits/remove_const.hpp> | |
#include <boost/ref.hpp> | |
namespace boost { namespace spirit { namespace karma | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// reference is a generator that references another generator (its Subject) | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject> | |
struct reference : generator<reference<Subject> > | |
{ | |
typedef mpl::int_<generator_properties::all_properties> properties; | |
typedef Subject subject_type; | |
reference(Subject& subject) | |
: ref(subject) {} | |
template <typename Context, typename Unused> | |
struct attribute : Subject::template attribute<Context, Unused> {}; | |
// Default overload, used whenever the attribute is not unused and not | |
// used from an aliased rule. | |
template <typename OutputIterator, typename Context | |
, typename Delimiter, typename Attribute> | |
bool generate(OutputIterator& sink, Context& context | |
, Delimiter const& delim, Attribute const& attr) const | |
{ | |
return ref.get().generate(sink, context, delim, attr); | |
} | |
// This overload gets called from an aliased rule only, we take the | |
// attribute from the context provided from the wrapper rule. | |
template <typename OutputIterator, typename Context | |
, typename Delimiter> | |
bool generate(OutputIterator& sink, Context& context | |
, Delimiter const& delim, unused_type) const | |
{ | |
return ref.get().generate(sink, context, delim, context.attributes); | |
} | |
// This overload is used whenever no attribute is given and it is used | |
// not from an aliased rule. | |
template <typename OutputIterator, typename Delimiter> | |
bool generate(OutputIterator& sink, unused_type | |
, Delimiter const& delim, unused_type) const | |
{ | |
return ref.get().generate(sink, unused, delim, unused); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
// the reference is transparent (does not add any info) | |
return ref.get().what(context); | |
} | |
boost::reference_wrapper<Subject> ref; | |
}; | |
}}} | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Attribute, typename Context | |
, typename Iterator> | |
struct handles_container<karma::reference<Subject>, Attribute | |
, Context, Iterator> | |
: handles_container<typename remove_const<Subject>::type, Attribute | |
, Context, Iterator> | |
{}; | |
}}} | |
#endif |