| // Copyright (c) 2001-2010 Joel de Guzman |
| // Copyright (c) 2001-2010 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_KLEENE_MAR_03_2007_0337AM) |
| #define BOOST_SPIRIT_KARMA_KLEENE_MAR_03_2007_0337AM |
| |
| #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/karma/detail/attributes.hpp> |
| |
| #include <boost/type_traits/add_const.hpp> |
| |
| namespace boost { namespace spirit |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // Enablers |
| /////////////////////////////////////////////////////////////////////////// |
| template <> |
| struct use_operator<karma::domain, proto::tag::dereference> // enables *g |
| : mpl::true_ {}; |
| }} |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| namespace boost { namespace spirit { namespace karma |
| { |
| template <typename Subject, typename Strict, typename Derived> |
| struct base_kleene : 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) const |
| { |
| // Ignore return value, failing subject generators are just |
| // skipped. This allows to selectively generate items in the |
| // provided attribute. |
| bool r = subject.generate(sink, ctx, d, attr); |
| return !Strict::value || r; |
| } |
| |
| template <typename OutputIterator, typename Context, typename Delimiter> |
| bool generate_subject(OutputIterator& sink, Context& ctx |
| , Delimiter const& d, unused_type) 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. |
| return subject.generate(sink, ctx, d, unused); |
| } |
| |
| public: |
| typedef Subject subject_type; |
| typedef typename subject_type::properties properties; |
| |
| // Build a std::vector from the subject's 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, Context, Iterator>::type |
| > |
| {}; |
| |
| base_kleene(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); |
| |
| // kleene fails only if the underlying output fails |
| for (/**/; detail::sink_is_good(sink) && !traits::compare(it, end); |
| traits::next(it)) |
| { |
| if (!generate_subject(sink, ctx, d, traits::deref(it))) |
| break; |
| } |
| return detail::sink_is_good(sink); |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| return info("kleene", subject.what(context)); |
| } |
| |
| Subject subject; |
| }; |
| |
| template <typename Subject> |
| struct kleene |
| : base_kleene<Subject, mpl::false_, kleene<Subject> > |
| { |
| typedef base_kleene<Subject, mpl::false_, kleene> base_kleene_; |
| |
| kleene(Subject const& subject) |
| : base_kleene_(subject) {} |
| }; |
| |
| template <typename Subject> |
| struct strict_kleene |
| : base_kleene<Subject, mpl::true_, strict_kleene<Subject> > |
| { |
| typedef base_kleene<Subject, mpl::true_, strict_kleene> base_kleene_; |
| |
| strict_kleene(Subject const& subject) |
| : base_kleene_(subject) {} |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Generator generators: make_xxx function (objects) |
| /////////////////////////////////////////////////////////////////////////// |
| namespace detail |
| { |
| template <typename Subject, bool strict_mode = false> |
| struct make_kleene |
| : make_unary_composite<Subject, kleene> |
| {}; |
| |
| template <typename Subject> |
| struct make_kleene<Subject, true> |
| : make_unary_composite<Subject, strict_kleene> |
| {}; |
| } |
| |
| template <typename Subject, typename Modifiers> |
| struct make_composite<proto::tag::dereference, Subject, Modifiers> |
| : detail::make_kleene<Subject, detail::get_stricttag<Modifiers>::value> |
| {}; |
| }}} |
| |
| namespace boost { namespace spirit { namespace traits |
| { |
| template <typename Subject> |
| struct has_semantic_action<karma::kleene<Subject> > |
| : unary_has_semantic_action<Subject> {}; |
| |
| template <typename Subject> |
| struct has_semantic_action<karma::strict_kleene<Subject> > |
| : unary_has_semantic_action<Subject> {}; |
| }}} |
| |
| #endif |