site_set_base.hh

// Copyright (C) 2007, 2008, 2009 EPITA Research and Development Laboratory (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena 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 Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to produce
// an executable, this file does not by itself cause the resulting
// executable to be covered by the GNU General Public License.  This
// exception does not however invalidate any other reasons why the
// executable file might be covered by the GNU General Public License.

#ifndef MLN_CORE_INTERNAL_SITE_SET_BASE_HH
# define MLN_CORE_INTERNAL_SITE_SET_BASE_HH


# include <mln/core/concept/site_set.hh>
# include <mln/core/concept/site_proxy.hh>


namespace mln
{

  namespace internal
  {


    template <typename P, typename E>
    struct site_set_base_ : public Site_Set<E>
    {
      typedef typename subject<P>::ret site;

      bool is_empty() const;

    protected:
      site_set_base_();

    private:
      // Default impl based on the number of sites.  It can be
      // overridden in subclasses that do not feature the 'nsites'
      // method.
      bool is_empty_() const;
    };


# ifndef MLN_INCLUDE_ONLY

    template <typename P, typename E>
    inline
    site_set_base_<P,E>::site_set_base_()
    {
    }

    template <typename P, typename E>
    inline
    bool
    site_set_base_<P,E>::is_empty() const
    {
      return exact(this)->is_empty_();
    }

    template <typename P, typename E>
    inline
    bool
    site_set_base_<P,E>::is_empty_() const
    {
      mlc_is(mln_trait_site_set_nsites(E),
             trait::site_set::nsites::known)::check();
      return exact(this)->nsites() == 0;
    }

# endif // ! MLN_INCLUDE_ONLY

  } // end of namespace mln::internal

} // end of namespace mln


#endif // ! MLN_CORE_INTERNAL_SITE_SET_BASE_HH