// 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_ACTION_MAR_07_2007_0851AM) | |
#define BOOST_SPIRIT_KARMA_ACTION_MAR_07_2007_0851AM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/karma/detail/attributes.hpp> | |
#include <boost/spirit/home/support/argument.hpp> | |
#include <boost/spirit/home/support/context.hpp> | |
#include <boost/spirit/home/support/unused.hpp> | |
#include <boost/spirit/home/support/info.hpp> | |
#include <boost/spirit/home/support/action_dispatch.hpp> | |
#include <boost/spirit/home/support/has_semantic_action.hpp> | |
#include <boost/spirit/home/support/handles_container.hpp> | |
#include <boost/spirit/home/karma/domain.hpp> | |
#include <boost/spirit/home/karma/meta_compiler.hpp> | |
#include <boost/spirit/home/karma/generator.hpp> | |
#include <boost/mpl/bool.hpp> | |
#include <boost/mpl/if.hpp> | |
#include <boost/type_traits/remove_const.hpp> | |
#include <boost/type_traits/is_same.hpp> | |
namespace boost { namespace spirit { namespace karma | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
BOOST_PP_REPEAT(SPIRIT_ARGUMENTS_LIMIT, SPIRIT_USING_ARGUMENT, _) | |
template <typename Subject, typename Action> | |
struct action : unary_generator<action<Subject, Action> > | |
{ | |
typedef Subject subject_type; | |
typedef typename subject_type::properties properties; | |
template <typename Context, typename Iterator> | |
struct attribute | |
: traits::attribute_of<Subject, Context, Iterator> | |
{}; | |
action(Subject const& subject, Action f) | |
: subject(subject), f(f) {} | |
template < | |
typename OutputIterator, typename Context, typename Delimiter | |
, typename Attribute> | |
bool generate(OutputIterator& sink, Context& ctx, Delimiter const& d | |
, Attribute const& attr_) const | |
{ | |
typedef typename attribute<Context, unused_type>::type attr_type; | |
typedef traits::make_attribute<attr_type, Attribute> make_attribute; | |
// create a attribute if none is supplied | |
// this creates a _copy_ of the attribute because the semantic | |
// action will likely change parts of this | |
typedef traits::transform_attribute< | |
typename make_attribute::type, attr_type, domain> transform; | |
typename transform::type attr = | |
traits::pre_transform<domain, attr_type>(make_attribute::call(attr_)); | |
// call the function, passing the attribute, the context and a bool | |
// flag that the client can set to false to fail generating. | |
return traits::action_dispatch<Subject>()(f, attr, ctx) && | |
subject.generate(sink, ctx, d, attr); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
// the action is transparent (does not add any info) | |
return subject.what(context); | |
} | |
subject_type subject; | |
Action f; | |
}; | |
}}} | |
/////////////////////////////////////////////////////////////////////////////// | |
namespace boost { namespace spirit | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// Karma action meta-compiler | |
template <> | |
struct make_component<karma::domain, tag::action> | |
{ | |
template <typename Sig> | |
struct result; | |
template <typename This, typename Elements, typename Modifiers> | |
struct result<This(Elements, Modifiers)> | |
{ | |
typedef typename | |
remove_const<typename Elements::car_type>::type | |
subject_type; | |
typedef typename | |
remove_const<typename Elements::cdr_type::car_type>::type | |
action_type; | |
typedef karma::action<subject_type, action_type> type; | |
}; | |
template <typename Elements> | |
typename result<make_component(Elements, unused_type)>::type | |
operator()(Elements const& elements, unused_type) const | |
{ | |
typename result<make_component(Elements, unused_type)>::type | |
result(elements.car, elements.cdr.car); | |
return result; | |
} | |
}; | |
}} | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Action> | |
struct has_semantic_action<karma::action<Subject, Action> > | |
: mpl::true_ {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Action, typename Attribute | |
, typename Context, typename Iterator> | |
struct handles_container<karma::action<Subject, Action>, Attribute | |
, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
}}} | |
#endif |