Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2001-2011 Joel de Guzman
Chris@16: 
Chris@16:     Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16:     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: =============================================================================*/
Chris@16: #if !defined(SPIRIT_PERMUTATION_OR_MARCH_13_2007_1145PM)
Chris@16: #define SPIRIT_PERMUTATION_OR_MARCH_13_2007_1145PM
Chris@16: 
Chris@16: #if defined(_MSC_VER)
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/spirit/home/qi/meta_compiler.hpp>
Chris@16: #include <boost/spirit/home/qi/detail/permute_function.hpp>
Chris@16: #include <boost/spirit/home/qi/detail/attributes.hpp>
Chris@16: #include <boost/spirit/home/support/algorithm/any_if_ns.hpp>
Chris@16: #include <boost/spirit/home/support/detail/what_function.hpp>
Chris@16: #include <boost/spirit/home/support/has_semantic_action.hpp>
Chris@16: #include <boost/spirit/home/support/handles_container.hpp>
Chris@16: #include <boost/spirit/home/support/info.hpp>
Chris@16: #include <boost/fusion/include/size.hpp>
Chris@16: #include <boost/optional.hpp>
Chris@16: #include <boost/foreach.hpp>
Chris@16: #include <boost/array.hpp>
Chris@16: 
Chris@16: namespace boost { namespace spirit
Chris@16: {
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Enablers
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <>
Chris@16:     struct use_operator<qi::domain, proto::tag::bitwise_xor> // enables ^
Chris@16:       : mpl::true_ {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct flatten_tree<qi::domain, proto::tag::bitwise_xor> // flattens ^
Chris@16:       : mpl::true_ {};
Chris@16: }}
Chris@16: 
Chris@16: namespace boost { namespace spirit { namespace qi
Chris@16: {
Chris@16:     template <typename Elements>
Chris@16:     struct permutation : nary_parser<permutation<Elements> >
Chris@16:     {
Chris@16:         template <typename Context, typename Iterator>
Chris@16:         struct attribute
Chris@16:         {
Chris@16:             // Put all the element attributes in a tuple,
Chris@16:             // wrapping each element in a boost::optional
Chris@16:             typedef typename traits::build_attribute_sequence<
Chris@16:                 Elements, Context, traits::permutation_attribute_transform
Chris@16:               , Iterator, qi::domain
Chris@16:             >::type all_attributes;
Chris@16: 
Chris@16:             // Now, build a fusion vector over the attributes. Note
Chris@16:             // that build_fusion_vector 1) removes all unused attributes
Chris@16:             // and 2) may return unused_type if all elements have
Chris@16:             // unused_type(s).
Chris@16:             typedef typename
Chris@16:                 traits::build_fusion_vector<all_attributes>::type
Chris@16:             type;
Chris@16:         };
Chris@16: 
Chris@16:         permutation(Elements const& elements_)
Chris@16:           : elements(elements_) {}
Chris@16: 
Chris@16:         template <typename Iterator, typename Context
Chris@16:           , typename Skipper, typename Attribute>
Chris@16:         bool parse(Iterator& first, Iterator const& last
Chris@16:           , Context& context, Skipper const& skipper
Chris@16:           , Attribute& attr_) const
Chris@16:         {
Chris@16:             typedef traits::attribute_not_unused<Context, Iterator> predicate;
Chris@16:             detail::permute_function<Iterator, Context, Skipper>
Chris@16:                 f(first, last, context, skipper);
Chris@16: 
Chris@16:             boost::array<bool, fusion::result_of::size<Elements>::value> flags;
Chris@16:             BOOST_FOREACH(bool& taken, flags)
Chris@16:             {
Chris@16:                 taken = false;
Chris@16:             }
Chris@16: 
Chris@16:             // wrap the attribute in a tuple if it is not a tuple
Chris@16:             typename traits::wrap_if_not_tuple<Attribute>::type attr_local(attr_);
Chris@16: 
Chris@16:             // We have a bool array 'flags' with one flag for each parser.
Chris@16:             // permute_function sets the slot to true when the corresponding
Chris@16:             // parser successful matches. We loop until there are no more
Chris@16:             // successful parsers.
Chris@16: 
Chris@16:             bool result = false;
Chris@16:             f.taken = flags.begin();
Chris@16:             while (spirit::any_if_ns(elements, attr_local, f, predicate()))
Chris@16:             {
Chris@16:                 f.taken = flags.begin();
Chris@16:                 result = true;
Chris@16:             }
Chris@16:             return result;
Chris@16:         }
Chris@16: 
Chris@16:         template <typename Context>
Chris@16:         info what(Context& context) const
Chris@16:         {
Chris@16:             info result("permutation");
Chris@16:             fusion::for_each(elements,
Chris@16:                 spirit::detail::what_function<Context>(result, context));
Chris@16:             return result;
Chris@16:         }
Chris@16: 
Chris@16:         Elements elements;
Chris@16:     };
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Parser generators: make_xxx function (objects)
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Elements, typename Modifiers>
Chris@16:     struct make_composite<proto::tag::bitwise_xor, Elements, Modifiers>
Chris@16:       : make_nary_composite<Elements, permutation>
Chris@16:     {};
Chris@16: }}}
Chris@16: 
Chris@16: namespace boost { namespace spirit { namespace traits
Chris@16: {
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // We specialize this for permutation (see support/attributes.hpp).
Chris@16:     // For permutation, we only wrap the attribute in a tuple IFF
Chris@16:     // it is not already a fusion tuple.
Chris@16:     template <typename Elements, typename Attribute>
Chris@16:     struct pass_attribute<qi::permutation<Elements>, Attribute>
Chris@16:       : wrap_if_not_tuple<Attribute> {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Elements>
Chris@16:     struct has_semantic_action<qi::permutation<Elements> >
Chris@16:       : nary_has_semantic_action<Elements> {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Elements, typename Attribute, typename Context
Chris@16:       , typename Iterator>
Chris@16:     struct handles_container<qi::permutation<Elements>, Attribute, Context
Chris@16:       , Iterator>
Chris@16:       : nary_handles_container<Elements, Attribute, Context, Iterator> {};
Chris@16: }}}
Chris@16: 
Chris@16: #endif