// 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_POSITIVE_MAR_03_2007_0945PM) | |
#define BOOST_SPIRIT_KARMA_POSITIVE_MAR_03_2007_0945PM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/karma/domain.hpp> | |
#include <boost/spirit/home/karma/generator.hpp> | |
#include <boost/spirit/home/karma/meta_compiler.hpp> | |
#include <boost/spirit/home/karma/detail/output_iterator.hpp> | |
#include <boost/spirit/home/karma/detail/get_stricttag.hpp> | |
#include <boost/spirit/home/support/info.hpp> | |
#include <boost/spirit/home/support/unused.hpp> | |
#include <boost/spirit/home/support/container.hpp> | |
#include <boost/spirit/home/support/has_semantic_action.hpp> | |
#include <boost/spirit/home/support/handles_container.hpp> | |
#include <boost/spirit/home/karma/detail/attributes.hpp> | |
#include <boost/type_traits/add_const.hpp> | |
namespace boost { namespace spirit | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// Enablers | |
/////////////////////////////////////////////////////////////////////////// | |
template <> | |
struct use_operator<karma::domain, proto::tag::unary_plus> // enables +g | |
: mpl::true_ {}; | |
}} | |
/////////////////////////////////////////////////////////////////////////////// | |
namespace boost { namespace spirit { namespace karma | |
{ | |
template <typename Subject, typename Strict, typename Derived> | |
struct base_plus : unary_generator<Derived> | |
{ | |
private: | |
template < | |
typename OutputIterator, typename Context, typename Delimiter | |
, typename Attribute> | |
bool generate_subject(OutputIterator& sink, Context& ctx | |
, Delimiter const& d, Attribute const& attr, bool& result) const | |
{ | |
// Ignore return value, failing subject generators are just | |
// skipped. This allows to selectively generate items in the | |
// provided attribute. | |
if (subject.generate(sink, ctx, d, attr)) { | |
result = true; | |
return true; | |
} | |
return !Strict::value; | |
} | |
template <typename OutputIterator, typename Context, typename Delimiter> | |
bool generate_subject(OutputIterator& sink, Context& ctx | |
, Delimiter const& d, unused_type, bool& result) const | |
{ | |
// There is no way to distinguish a failed generator from a | |
// generator to be skipped. We assume the user takes responsibility | |
// for ending the loop if no attribute is specified. | |
if (subject.generate(sink, ctx, d, unused)) { | |
result = true; | |
return true; | |
} | |
return false; | |
} | |
public: | |
typedef Subject subject_type; | |
typedef typename subject_type::properties properties; | |
// Build a std::vector from the subjects attribute. Note | |
// that build_std_vector may return unused_type if the | |
// subject's attribute is an unused_type. | |
template <typename Context, typename Iterator> | |
struct attribute | |
: traits::build_std_vector< | |
typename traits::attribute_of<subject_type, Context, Iterator>::type | |
> | |
{}; | |
base_plus(Subject const& subject) | |
: subject(subject) {} | |
template < | |
typename OutputIterator, typename Context, typename Delimiter | |
, typename Attribute> | |
bool generate(OutputIterator& sink, Context& ctx | |
, Delimiter const& d, Attribute const& attr) const | |
{ | |
typedef typename traits::container_iterator< | |
typename add_const<Attribute>::type | |
>::type iterator_type; | |
iterator_type it = traits::begin(attr); | |
iterator_type end = traits::end(attr); | |
// plus fails if the parameter is empty | |
if (traits::compare(it, end)) | |
return false; | |
// from now on plus fails if the underlying output fails or overall | |
// no subject generators succeeded | |
bool result = false; | |
for (/**/; detail::sink_is_good(sink) && !traits::compare(it, end); | |
traits::next(it)) | |
{ | |
if (!generate_subject(sink, ctx, d, traits::deref(it), result)) | |
break; | |
} | |
return result && detail::sink_is_good(sink); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
return info("plus", subject.what(context)); | |
} | |
Subject subject; | |
}; | |
template <typename Subject> | |
struct plus | |
: base_plus<Subject, mpl::false_, plus<Subject> > | |
{ | |
typedef base_plus<Subject, mpl::false_, plus> base_plus_; | |
plus(Subject const& subject) | |
: base_plus_(subject) {} | |
}; | |
template <typename Subject> | |
struct strict_plus | |
: base_plus<Subject, mpl::true_, strict_plus<Subject> > | |
{ | |
typedef base_plus<Subject, mpl::true_, strict_plus> base_plus_; | |
strict_plus(Subject const& subject) | |
: base_plus_(subject) {} | |
}; | |
/////////////////////////////////////////////////////////////////////////// | |
// Generator generators: make_xxx function (objects) | |
/////////////////////////////////////////////////////////////////////////// | |
namespace detail | |
{ | |
template <typename Elements, bool strict_mode = false> | |
struct make_plus | |
: make_unary_composite<Elements, plus> | |
{}; | |
template <typename Elements> | |
struct make_plus<Elements, true> | |
: make_unary_composite<Elements, strict_plus> | |
{}; | |
} | |
template <typename Elements, typename Modifiers> | |
struct make_composite<proto::tag::unary_plus, Elements, Modifiers> | |
: detail::make_plus<Elements, detail::get_stricttag<Modifiers>::value> | |
{}; | |
}}} | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject> | |
struct has_semantic_action<karma::plus<Subject> > | |
: unary_has_semantic_action<Subject> {}; | |
template <typename Subject> | |
struct has_semantic_action<karma::strict_plus<Subject> > | |
: unary_has_semantic_action<Subject> {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Attribute, typename Context | |
, typename Iterator> | |
struct handles_container<karma::plus<Subject>, Attribute | |
, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
template <typename Subject, typename Attribute, typename Context | |
, typename Iterator> | |
struct handles_container<karma::strict_plus<Subject>, Attribute | |
, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
}}} | |
#endif |