Ticket #1654: recursive_variant.hpp.patch

recursive_variant.hpp

@@ -22 +22 @@
 #include "boost/mpl/aux_/lambda_arity_param.hpp"
 
 #if !defined(BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT)
+#   include "boost/mpl/equal.hpp"
 #   include "boost/mpl/eval_if.hpp"
 #   include "boost/mpl/identity.hpp"
+#   include "boost/mpl/if.hpp"
 #   include "boost/mpl/protect.hpp"
 #   include "boost/mpl/transform.hpp"
+#   include "boost/type_traits/is_same.hpp"
 #else
 #   include "boost/preprocessor/cat.hpp"
 #   include "boost/preprocessor/repeat.hpp"
@@ -98 +101 @@
 
 public: // metafunction result
 
-    typedef ::boost::variant< types > type;
+    typedef typename mpl::if_<
+          mpl::equal<initial_types, types, ::boost::is_same<mpl::_1, mpl::_2> >
+        , ::boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >
+        , ::boost::variant< over_sequence<types> >
+        >::type type;
 
 #else // defined(BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT)