| // Copyright (c) 2001-2010 Hartmut Kaiser |
| // Copyright (c) 2001-2010 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_KARMA_LIST_MAY_01_2007_0229PM) |
| #define SPIRIT_KARMA_LIST_MAY_01_2007_0229PM |
| |
| #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> |
| |
| namespace boost { namespace spirit |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // Enablers |
| /////////////////////////////////////////////////////////////////////////// |
| template <> |
| struct use_operator<karma::domain, proto::tag::modulus> // enables g % d |
| : mpl::true_ {}; |
| }} |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| namespace boost { namespace spirit { namespace karma |
| { |
| template <typename Left, typename Right, typename Strict, typename Derived> |
| struct base_list : binary_generator<Derived> |
| { |
| private: |
| // iterate over the given container until its exhausted or the embedded |
| // (left) generator succeeds |
| template < |
| typename OutputIterator, typename Context, typename Delimiter |
| , typename Iterator, typename Attribute> |
| bool generate_left(OutputIterator& sink, Context& ctx |
| , Delimiter const& d, Iterator& it, Iterator& end, Attribute const&) const |
| { |
| if (Strict::value) { |
| if (!traits::compare(it, end)) |
| return left.generate(sink, ctx, d, traits::deref(it)); |
| } |
| else { |
| // Failing subject generators are just skipped. This allows to |
| // selectively generate items in the provided attribute. |
| while (!traits::compare(it, end)) |
| { |
| if (left.generate(sink, ctx, d, traits::deref(it))) |
| return true; |
| traits::next(it); |
| } |
| } |
| return false; |
| } |
| |
| template < |
| typename OutputIterator, typename Context, typename Delimiter |
| , typename Iterator> |
| bool generate_left(OutputIterator& sink, Context& ctx |
| , Delimiter const& d, Iterator&, Iterator&, 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 left.generate(sink, ctx, d, unused); |
| } |
| |
| public: |
| typedef Left left_type; |
| typedef Right right_type; |
| |
| typedef mpl::int_< |
| left_type::properties::value |
| | right_type::properties::value |
| | generator_properties::buffering |
| | generator_properties::counting |
| > properties; |
| |
| // Build a std::vector from the LHS'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<Left, Context, Iterator>::type> |
| {}; |
| |
| base_list(Left const& left, Right const& right) |
| : left(left), right(right) |
| {} |
| |
| 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); |
| |
| if (generate_left(sink, ctx, d, it, end, attr)) |
| { |
| for (traits::next(it); !traits::compare(it, end); traits::next(it)) |
| { |
| // wrap the given output iterator as generate_left might fail |
| detail::enable_buffering<OutputIterator> buffering(sink); |
| { |
| detail::disable_counting<OutputIterator> nocounting(sink); |
| |
| if (!right.generate(sink, ctx, d, unused)) |
| return false; // shouldn't happen |
| |
| if (!generate_left(sink, ctx, d, it, end, attr)) |
| break; // return true as one item succeeded |
| } |
| buffering.buffer_copy(); |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| return info("list", |
| std::make_pair(left.what(context), right.what(context))); |
| } |
| |
| Left left; |
| Right right; |
| }; |
| |
| template <typename Left, typename Right> |
| struct list |
| : base_list<Left, Right, mpl::false_, list<Left, Right> > |
| { |
| typedef base_list<Left, Right, mpl::false_, list> base_list_; |
| |
| list(Left const& left, Right const& right) |
| : base_list_(left, right) {} |
| }; |
| |
| template <typename Left, typename Right> |
| struct strict_list |
| : base_list<Left, Right, mpl::true_, strict_list<Left, Right> > |
| { |
| typedef base_list<Left, Right, mpl::true_, strict_list> base_list_; |
| |
| strict_list (Left const& left, Right const& right) |
| : base_list_(left, right) {} |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Generator generators: make_xxx function (objects) |
| /////////////////////////////////////////////////////////////////////////// |
| namespace detail |
| { |
| template <typename Subject, bool strict_mode = false> |
| struct make_list |
| : make_binary_composite<Subject, list> |
| {}; |
| |
| template <typename Subject> |
| struct make_list<Subject, true> |
| : make_binary_composite<Subject, strict_list> |
| {}; |
| } |
| |
| template <typename Subject, typename Modifiers> |
| struct make_composite<proto::tag::modulus, Subject, Modifiers> |
| : detail::make_list<Subject, detail::get_stricttag<Modifiers>::value> |
| {}; |
| }}} |
| |
| namespace boost { namespace spirit { namespace traits |
| { |
| template <typename Left, typename Right> |
| struct has_semantic_action<karma::list<Left, Right> > |
| : binary_has_semantic_action<Left, Right> {}; |
| |
| template <typename Left, typename Right> |
| struct has_semantic_action<karma::strict_list<Left, Right> > |
| : binary_has_semantic_action<Left, Right> {}; |
| }}} |
| |
| #endif |