整理

include/boost/mpl/aux_/arity.hpp

@@ -0,0 +1,39 @@
+
+#ifndef BOOST_MPL_AUX_ARITY_HPP_INCLUDED
+#define BOOST_MPL_AUX_ARITY_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/aux_/config/dtp.hpp>
+
+#if defined(BOOST_MPL_CFG_BROKEN_DEFAULT_PARAMETERS_IN_NESTED_TEMPLATES)
+
+#   include <boost/mpl/aux_/nttp_decl.hpp>
+#   include <boost/mpl/aux_/config/static_constant.hpp>
+
+namespace boost { namespace mpl { namespace aux {
+
+// agurt, 15/mar/02: it's possible to implement the template so that it will 
+// "just work" and do not require any specialization, but not on the compilers
+// that require the arity workaround in the first place
+template< typename F, BOOST_MPL_AUX_NTTP_DECL(int, N) >
+struct arity
+{
+    BOOST_STATIC_CONSTANT(int, value = N);
+};
+
+}}}
+
+#endif // BOOST_MPL_CFG_BROKEN_DEFAULT_PARAMETERS_IN_NESTED_TEMPLATES
+
+#endif // BOOST_MPL_AUX_ARITY_HPP_INCLUDED