整理

include/boost/mpl/aux_/fold_op.hpp

@@ -0,0 +1,37 @@
+
+#ifndef BOOST_MPL_AUX_FOLD_OP_HPP_INCLUDED
+#define BOOST_MPL_AUX_FOLD_OP_HPP_INCLUDED
+
+// Copyright Aleksey Gurtovoy 2001-2004
+//
+// 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)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+
+// $Id$
+// $Date$
+// $Revision$
+
+#include <boost/mpl/apply.hpp>
+
+namespace boost { namespace mpl { namespace aux {
+
+// hand-written version is more efficient than bind/lambda expression
+template< typename Op >
+struct fold_op
+{
+    template< typename T1, typename T2 > struct apply
+    {
+        typedef typename apply2<
+              Op
+            , T1
+            , typename T2::type
+            >::type type;
+    };
+};
+
+}}}
+
+#endif // BOOST_MPL_AUX_FOLD_OP_HPP_INCLUDED