branch for creating branch for fusion 2.1

[SVN r40237]
2007-10-21 00:52:09 +00:00
parent 7a6e82b7cf
commit 32f1c58ce7
476 changed files with 25709 additions and 0 deletions
--- a/include/boost/fusion/adapted/variant/variant_iterator.hpp
+++ b/include/boost/fusion/adapted/variant/variant_iterator.hpp
@ -0,0 +1,117 @@
+/*=============================================================================
+    Copyright (c) 2001-2006 Joel de Guzman
+    Copyright (c) 2005-2006 Dan Marsden
+
+    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_FUSION_VARIANT_ITERATOR_12112006_1617)
+#define BOOST_FUSION_VARIANT_ITERATOR_12112006_1617
+
+#include <boost/fusion/iterator/iterator_facade.hpp>
+
+#include <boost/mpl/next.hpp>
+#include <boost/mpl/int.hpp>
+#include <boost/mpl/distance.hpp>
+#include <boost/mpl/deref.hpp>
+#include <boost/mpl/eval_if.hpp>
+#include <boost/type_traits/is_const.hpp>
+#include <boost/type_traits/add_const.hpp>
+#include <boost/type_traits/add_reference.hpp>
+#include <boost/variant/get.hpp>
+#include <boost/detail/workaround.hpp>
+
+namespace boost { namespace fusion
+{
+    struct forward_traversal_tag;
+
+    template<typename Variant, typename MPLIterator>
+    struct variant_iterator
+        : iterator_facade<variant_iterator<Variant, MPLIterator>, forward_traversal_tag>
+    {
+        typedef Variant variant_type;
+        typedef MPLIterator iterator;
+
+        variant_iterator(Variant& var)
+            : var_(var) {}
+        Variant& var_;
+
+        template<typename Iterator>
+        struct next
+        {
+            typedef variant_iterator<
+                typename Iterator::variant_type,
+                typename mpl::next<typename Iterator::iterator>::type> type;
+
+            static type
+            call(Iterator const& i)
+            {
+                return type(i.var_);
+            }
+        };
+
+        template<typename I1, typename I2>
+        struct distance
+            : mpl::distance<
+            typename I1::iterator,
+            typename I2::iterator>
+        {
+            typedef typename mpl::distance<
+                typename I1::iterator,
+                typename I2::iterator>::type type;
+
+            static type call(I1 const& i1, I2 const& i2)
+            {
+                return type();
+            }
+        };
+
+        template<typename Iterator>
+        struct value_of
+            : mpl::deref<typename Iterator::iterator>
+        {};
+
+        template <typename Iterator>
+        struct deref
+        {
+            typedef typename
+                mpl::eval_if<
+                    is_const<typename Iterator::variant_type>
+                  , add_const<typename mpl::deref<typename Iterator::iterator>::type>
+                  , mpl::deref<typename Iterator::iterator>
+                >::type
+            value_type;
+
+            typedef typename
+                add_reference<value_type>::type
+            type;
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1400)
+// for some unknown reason (compiler bug) VC7.1 gets confused with
+// variant and optional get functions.
+            static type
+            call(Iterator const & it)
+            {
+                boost::detail::variant::get_visitor<type> v;
+                typedef typename mpl::deref<typename Iterator::iterator>::type type;
+                if (type* result = it.var_.apply_visitor(v))
+                    return *result;
+                it.var_ = type(); // prime the variant
+                return *it.var_.apply_visitor(v); // no-throw!
+            }
+#else
+            static type
+            call(Iterator const & it)
+            {
+                typedef typename mpl::deref<typename Iterator::iterator>::type type;
+                if (type* result = boost::get<type>(&it.var_))
+                    return *result;
+                it.var_ = type(); // prime the variant
+                return *boost::get<type>(&it.var_); // no-throw!
+            }
+#endif
+        };
+    };
+}}
+
+#endif