visitor_cast-fwd.hh

/* vim: set sw=4 sts=4 et foldmethod=syntax : */
 
/*
 * Copyright (c) 2008, 2009, 2011 Ciaran McCreesh
 *
 * This file is part of the Paludis package manager. Paludis is free software;
 * you can redistribute it and/or modify it under the terms of the GNU General
 * Public License version 2, as published by the Free Software Foundation.
 *
 * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA  02111-1307  USA
 */
 
#ifndef PALUDIS_GUARD_PALUDIS_UTIL_VISITOR_CAST_FWD_HH
#define PALUDIS_GUARD_PALUDIS_UTIL_VISITOR_CAST_FWD_HH 1
 
#include <paludis/util/attributes.hh>
#include <type_traits>
 
namespace paludis
{
    template <typename To_, typename From_,
              typename = typename std::enable_if<std::is_base_of<From_, To_>::value>::type>
    To_ * visitor_cast(From_ &) PALUDIS_ATTRIBUTE((warn_unused_result));
}
 
#endif