alpha.hh

// Copyright (C) 2001, 2002, 2003, 2004  EPITA Research and Development Laboratory
//
// This file is part of the Olena Library.  This library 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.
//
// This library 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 library; see the file COPYING.  If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
// MA 02111-1307, USA.
//
// As a special exception, you may use this file as part of a free
// software library without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
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#ifndef OLENA_TOPO_COMBINATORIAL_MAP_INTERNAL_ALPHA_HH
# define OLENA_TOPO_COMBINATORIAL_MAP_INTERNAL_ALPHA_HH

namespace oln {

  namespace topo {

    namespace combinatorial_map {

      namespace internal {
        template <class U>
        struct alpha
        {
          static U
          result(const U & d)
          {
            return d + ((d & 1) << 1) - 1;
          }
        };

      } // end of namespace internal

    } // end of namespace combinatorial_map

  } // end of namespace topo

} // end of namespace oln

#endif // ! OLENA_TOPO_COMBINATORIAL_MAP_INTERNAL_ALPHA_HH

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