couple.hh

// Copyright (C) 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_ACCU_INTERNAL_COUPLE_HH
# define MLN_ACCU_INTERNAL_COUPLE_HH


# include <utility>

# include <mln/core/concept/accumulator.hh>
# include <mln/accu/internal/base.hh>

# include <mln/metal/equal.hh>


namespace mln
{

  namespace accu
  {

    namespace internal
    {

      template <typename A1, typename A2, typename R, typename E>
      struct couple
        : base<R,E>,
          mlc_equal(mln_argument(A1), mln_argument(A2))::check_t
      {
        typedef mln_argument(A1) argument;

        void init();
        void take_as_init(const argument& t);
        void take(const argument& t);
        void take(const E& other);

        bool is_valid() const;

        A1& first();
        A2& second();
        const A1& first() const;
        const A2& second() const;

        protected:
        couple();

        A1 a1_;
        A2 a2_;
      };


# ifndef MLN_INCLUDE_ONLY

      template <typename A1, typename A2, typename R, typename E>
      inline
      couple<A1,A2,R,E>::couple()
      {
        init();
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      void
      couple<A1,A2,R,E>::init()
      {
        a1_.init();
        a2_.init();
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      void
      couple<A1,A2,R,E>::take_as_init(const argument& t)
      {
        a1_.take_as_init(t);
        a2_.take_as_init(t);
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      void
      couple<A1,A2,R,E>::take(const argument& t)
      {
        a1_.take(t);
        a2_.take(t);
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      void
      couple<A1,A2,R,E>::take(const E& other)
      {
        a1_.take(other.a1_);
        a2_.take(other.a2_);
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      bool
      couple<A1,A2,R,E>::is_valid() const
      {
        return a1_.is_valid() && a2_.is_valid();
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      A1&
      couple<A1,A2,R,E>::first()
      {
        return a1_;
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      const A1&
      couple<A1,A2,R,E>::first() const
      {
        return a1_;
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      A2&
      couple<A1,A2,R,E>::second()
      {
        return a2_;
      }

      template <typename A1, typename A2, typename R, typename E>
      inline
      const A2&
      couple<A1,A2,R,E>::second() const
      {
        return a2_;
      }

# endif // ! MLN_INCLUDE_ONLY

    } // end of namespace mln::accu::internal

  } // end of namespace mln::accu

} // end of namespace mln


#endif // ! MLN_ACCU_INTERNAL_COUPLE_HH