| /*============================================================================= |
| 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_PERMUTATION_OR_MARCH_13_2007_1145PM) |
| #define SPIRIT_PERMUTATION_OR_MARCH_13_2007_1145PM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/spirit/home/qi/meta_compiler.hpp> |
| #include <boost/spirit/home/qi/detail/permute_function.hpp> |
| #include <boost/spirit/home/qi/detail/attributes.hpp> |
| #include <boost/spirit/home/support/algorithm/any_if_ns.hpp> |
| #include <boost/spirit/home/support/detail/what_function.hpp> |
| #include <boost/spirit/home/support/info.hpp> |
| #include <boost/fusion/include/size.hpp> |
| #include <boost/optional.hpp> |
| #include <boost/foreach.hpp> |
| #include <boost/array.hpp> |
| |
| namespace boost { namespace spirit |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // Enablers |
| /////////////////////////////////////////////////////////////////////////// |
| template <> |
| struct use_operator<qi::domain, proto::tag::bitwise_xor> // enables ^ |
| : mpl::true_ {}; |
| |
| template <> |
| struct flatten_tree<qi::domain, proto::tag::bitwise_xor> // flattens ^ |
| : mpl::true_ {}; |
| }} |
| |
| namespace boost { namespace spirit { namespace qi |
| { |
| template <typename Elements> |
| struct permutation : nary_parser<permutation<Elements> > |
| { |
| template <typename Context, typename Iterator> |
| struct attribute |
| { |
| // Put all the element attributes in a tuple, |
| // wrapping each element in a boost::optional |
| typedef typename traits::build_attribute_sequence< |
| Elements, Context, traits::build_optional, Iterator>::type |
| all_attributes; |
| |
| // Now, build a fusion vector over the attributes. Note |
| // that build_fusion_vector 1) removes all unused attributes |
| // and 2) may return unused_type if all elements have |
| // unused_type(s). |
| typedef typename |
| traits::build_fusion_vector<all_attributes>::type |
| type; |
| }; |
| |
| permutation(Elements const& elements) |
| : elements(elements) {} |
| |
| template <typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool parse(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& attr_) const |
| { |
| typedef traits::attribute_not_unused<Context, Iterator> predicate; |
| detail::permute_function<Iterator, Context, Skipper> |
| f(first, last, context, skipper); |
| |
| boost::array<bool, fusion::result_of::size<Elements>::value> flags; |
| BOOST_FOREACH(bool& taken, flags) |
| { |
| taken = false; |
| } |
| |
| // wrap the attribute in a tuple if it is not a tuple |
| typename traits::wrap_if_not_tuple<Attribute>::type attr(attr_); |
| |
| // We have a bool array 'flags' with one flag for each parser. |
| // permute_function sets the slot to true when the corresponding |
| // parser successful matches. We loop until there are no more |
| // successful parsers. |
| |
| bool result = false; |
| f.taken = flags.begin(); |
| while (spirit::any_if_ns(elements, attr, f, predicate())) |
| { |
| f.taken = flags.begin(); |
| result = true; |
| } |
| return result; |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| info result("permutation"); |
| fusion::for_each(elements, |
| spirit::detail::what_function<Context>(result, context)); |
| return result; |
| } |
| |
| Elements elements; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Parser generators: make_xxx function (objects) |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Elements, typename Modifiers> |
| struct make_composite<proto::tag::bitwise_xor, Elements, Modifiers> |
| : make_nary_composite<Elements, permutation> |
| {}; |
| }}} |
| |
| namespace boost { namespace spirit { namespace traits |
| { |
| // We specialize this for permutation (see support/attributes.hpp). |
| // For permutation, we only wrap the attribute in a tuple IFF |
| // it is not already a fusion tuple. |
| template <typename Elements, typename Attribute> |
| struct pass_attribute<qi::permutation<Elements>, Attribute> |
| : wrap_if_not_tuple<Attribute> {}; |
| |
| template <typename Elements> |
| struct has_semantic_action<qi::permutation<Elements> > |
| : nary_has_semantic_action<Elements> {}; |
| }}} |
| |
| #endif |