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+/*=============================================================================
+    Copyright (c) 1998-2003 Joel de Guzman
+    Copyright (c) 2001 Daniel Nuffer
+    Copyright (c) 2002 Hartmut Kaiser
+    http://spirit.sourceforge.net/
+
+  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_ALTERNATIVE_HPP)
+#define BOOST_SPIRIT_ALTERNATIVE_HPP
+
+#include <boost/spirit/home/classic/namespace.hpp>
+#include <boost/spirit/home/classic/core/parser.hpp>
+#include <boost/spirit/home/classic/core/primitives/primitives.hpp>
+#include <boost/spirit/home/classic/core/composite/composite.hpp>
+#include <boost/spirit/home/classic/meta/as_parser.hpp>
+
+namespace boost { namespace spirit {
+
+BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN
+
+    ///////////////////////////////////////////////////////////////////////////
+    //
+    //  alternative class
+    //
+    //      Handles expressions of the form:
+    //
+    //          a | b
+    //
+    //      where a and b are parsers. The expression returns a composite
+    //      parser that matches a or b. One (not both) of the operands may
+    //      be a literal char, wchar_t or a primitive string char const*,
+    //      wchar_t const*.
+    //
+    //      The expression is short circuit evaluated. b is never touched
+    //      when a is returns a successful match.
+    //
+    ///////////////////////////////////////////////////////////////////////////
+    struct alternative_parser_gen;
+    
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(push)
+#pragma warning(disable:4512) //assignment operator could not be generated
+#endif
+
+    template <typename A, typename B>
+    struct alternative
+    :   public binary<A, B, parser<alternative<A, B> > >
+    {
+        typedef alternative<A, B>               self_t;
+        typedef binary_parser_category          parser_category_t;
+        typedef alternative_parser_gen          parser_generator_t;
+        typedef binary<A, B, parser<self_t> >   base_t;
+    
+        alternative(A const& a, B const& b)
+        : base_t(a, b) {}
+    
+        template <typename ScannerT>
+        typename parser_result<self_t, ScannerT>::type
+        parse(ScannerT const& scan) const
+        {
+            typedef typename parser_result<self_t, ScannerT>::type result_t;
+            typedef typename ScannerT::iterator_t iterator_t;
+            { // scope for save
+                iterator_t save = scan.first;
+                if (result_t hit = this->left().parse(scan))
+                    return hit;
+                scan.first = save;
+            }
+            return this->right().parse(scan);
+        }
+    };
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(pop)
+#endif
+    
+    struct alternative_parser_gen
+    {
+        template <typename A, typename B>
+        struct result 
+        {
+            typedef 
+                alternative<
+                    typename as_parser<A>::type
+                  , typename as_parser<B>::type
+                > 
+            type;
+        };
+    
+        template <typename A, typename B>
+        static alternative<
+            typename as_parser<A>::type
+          , typename as_parser<B>::type
+        >
+        generate(A const& a, B const& b)
+        {
+            return alternative<BOOST_DEDUCED_TYPENAME as_parser<A>::type,
+                BOOST_DEDUCED_TYPENAME as_parser<B>::type>
+                    (as_parser<A>::convert(a), as_parser<B>::convert(b));
+        }
+    };
+    
+    template <typename A, typename B>
+    alternative<A, B>
+    operator|(parser<A> const& a, parser<B> const& b);
+    
+    template <typename A>
+    alternative<A, chlit<char> >
+    operator|(parser<A> const& a, char b);
+    
+    template <typename B>
+    alternative<chlit<char>, B>
+    operator|(char a, parser<B> const& b);
+    
+    template <typename A>
+    alternative<A, strlit<char const*> >
+    operator|(parser<A> const& a, char const* b);
+    
+    template <typename B>
+    alternative<strlit<char const*>, B>
+    operator|(char const* a, parser<B> const& b);
+    
+    template <typename A>
+    alternative<A, chlit<wchar_t> >
+    operator|(parser<A> const& a, wchar_t b);
+    
+    template <typename B>
+    alternative<chlit<wchar_t>, B>
+    operator|(wchar_t a, parser<B> const& b);
+    
+    template <typename A>
+    alternative<A, strlit<wchar_t const*> >
+    operator|(parser<A> const& a, wchar_t const* b);
+    
+    template <typename B>
+    alternative<strlit<wchar_t const*>, B>
+    operator|(wchar_t const* a, parser<B> const& b);
+
+BOOST_SPIRIT_CLASSIC_NAMESPACE_END
+
+}} // namespace BOOST_SPIRIT_CLASSIC_NS
+
+#endif
+
+#include <boost/spirit/home/classic/core/composite/impl/alternative.ipp>