comparison DEPENDENCIES/generic/include/boost/spirit/home/x3/support/context.hpp @ 102:f46d142149f5

Whoops, finish that update

+/*=============================================================================
+    Copyright (c) 2001-2014 Joel de Guzman
+    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_X3_CONTEXT_JAN_4_2012_1215PM)
+#define BOOST_SPIRIT_X3_CONTEXT_JAN_4_2012_1215PM
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/spirit/home/x3/support/unused.hpp>
+#include <boost/mpl/identity.hpp>
+
+namespace boost { namespace spirit { namespace x3
+{
+    template <typename ID, typename T, typename Next = unused_type>
+    struct context
+    {
+        context(T& val, Next const& next)
+            : val(val), next(next) {}
+
+        template <typename ID_, typename Unused = void>
+        struct get_result
+        {
+            typedef typename Next::template get_result<ID_>::type type;
+        };
+
+        template <typename Unused>
+        struct get_result<mpl::identity<ID>, Unused>
+        {
+            typedef T& type;
+        };
+
+        T& get(mpl::identity<ID>) const
+        {
+            return val;
+        }
+
+        template <typename ID_>
+        typename Next::template get_result<ID_>::type
+        get(ID_ id) const
+        {
+            return next.get(id);
+        }
+
+        T& val;
+        Next const& next;
+    };
+
+    template <typename ID, typename T>
+    struct context<ID, T, unused_type>
+    {
+        context(T& val)
+            : val(val) {}
+
+        context(T& val, unused_type)
+            : val(val) {}
+
+        template <typename ID_, typename Unused = void>
+        struct get_result
+        {
+            typedef unused_type type;
+        };
+
+        template <typename Unused>
+        struct get_result<mpl::identity<ID>, Unused>
+        {
+            typedef T& type;
+        };
+
+        T& get(mpl::identity<ID>) const
+        {
+            return val;
+        }
+
+        template <typename ID_>
+        unused_type
+        get(ID_) const
+        {
+            return unused;
+        }
+
+        T& val;
+    };
+
+    template <typename Tag, typename Context>
+    inline auto
+    get(Context const& context)
+        -> decltype(context.get(mpl::identity<Tag>()))
+    {
+        return context.get(mpl::identity<Tag>());
+    }
+
+    template <typename ID, typename T, typename Next>
+    inline context<ID, T, Next> make_context(T& val, Next const& next)
+    {
+        return context<ID, T, Next>(val, next);
+    }
+
+    template <typename ID, typename T>
+    inline context<ID, T> make_context(T& val)
+    {
+        return context<ID, T>(val);
+    }
+    
+    namespace detail
+    {
+        template <typename ID, typename T, typename Next, typename FoundVal>
+        inline Next const&
+        make_unique_context(T& val, Next const& next, FoundVal&)
+        {
+            return next;
+        }
+        
+        template <typename ID, typename T, typename Next>
+        inline context<ID, T, Next>
+        make_unique_context(T& val, Next const& next, unused_type)
+        {
+            return context<ID, T, Next>(val, next);
+        }
+    }
+    
+    template <typename ID, typename T, typename Next>
+    inline auto
+    make_unique_context(T& val, Next const& next)
+    {
+        return detail::make_unique_context<ID>(val, next, x3::get<ID>(next));
+    }
+}}}
+
+#endif