Imported existing code

libraries/include/boost/spirit/home/qi/operator/permutation.hpp

@@ -0,0 +1,96 @@
+/*=============================================================================
+    Copyright (c) 2001-2007 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
+
+#include <boost/spirit/home/qi/detail/permute_function.hpp>
+#include <boost/spirit/home/support/attribute_transform.hpp>
+#include <boost/spirit/home/support/algorithm/any.hpp>
+#include <boost/spirit/home/support/detail/what_function.hpp>
+#include <boost/fusion/include/vector.hpp>
+#include <boost/fusion/include/as_vector.hpp>
+#include <boost/fusion/include/size.hpp>
+#include <boost/optional.hpp>
+#include <boost/foreach.hpp>
+#include <boost/array.hpp>
+
+namespace boost { namespace spirit { namespace qi
+{
+    struct permutation
+    {
+        template <typename T>
+        struct transform_child
+        {
+            typedef boost::optional<T> type;
+        };
+
+        template <typename All, typename Filtered>
+        struct build_container
+        {
+            typedef
+                typename fusion::result_of::as_vector<Filtered>::type
+            type;
+        };
+
+        template <typename Component, typename Context, typename Iterator>
+        struct attribute :
+            build_fusion_sequence<permutation, Component, Iterator, Context>
+        {
+        };
+
+        template <
+            typename Component
+          , typename Iterator, typename Context
+          , typename Skipper, typename Attribute>
+        static bool parse(
+            Component const& component
+          , Iterator& first, Iterator const& last
+          , Context& context, Skipper const& skipper
+          , Attribute& attr)
+        {
+            detail::permute_function<Iterator, Context, Skipper>
+                f(first, last, context, skipper);
+
+            boost::array<
+                bool
+              , fusion::result_of::size<typename Component::elements_type>::value
+            >
+            slots;
+
+            BOOST_FOREACH(bool& taken, slots)
+            {
+                taken = false;
+            }
+
+            // We have a bool array 'slots' 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 = slots.begin();
+            while (spirit::any_ns(component.elements, attr, f))
+            {
+                f.taken = slots.begin();
+                result = true;
+            }
+            return result;
+        }
+
+        template <typename Component, typename Context>
+        static std::string what(Component const& component, Context const& ctx)
+        {
+            std::string result = "permutation[";
+            fusion::for_each(component.elements,
+                spirit::detail::what_function<Context>(result, ctx));
+            result += "]";
+            return result;
+        }
+    };
+}}}
+
+#endif