value_.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_TRAIT_VALUE__HH
# define MLN_TRAIT_VALUE__HH


# include <iostream>
# include <string>

# include <mln/metal/int.hh>
# include <mln/metal/math/pow.hh>
# include <mln/metal/if.hh>

# include <mln/trait/value/all.hh>
# include <mln/metal/math/pow.hh>
# include <mln/core/def/low_quant_nbits.hh>


# define mln_trait_value_nature(V) typename mln::trait::value_< V >::nature
# define mln_trait_value_nature_(V)         mln::trait::value_< V >::nature
# define mln_trait_value_kind(V)   typename mln::trait::value_< V >::kind
# define mln_trait_value_kind_(V)           mln::trait::value_< V >::kind
# define mln_trait_value_quant(V)  typename mln::trait::value_< V >::quant
# define mln_trait_value_quant_(V)          mln::trait::value_< V >::quant


# define mln_card(V)     mln::trait::value_< V >::card
# define mln_dim(V)      mln::trait::value_< V >::dim
# define mln_epsilon(V)  mln::trait::value_< V >::epsilon()
# define mln_max(V)      mln::trait::value_< V >::max()
# define mln_min(V)      mln::trait::value_< V >::min()
# define mln_nbits(V)    mln::trait::value_< V >::nbits


# define mln_trait_value_sum(V)   typename mln::trait::value_< V >::sum
# define mln_trait_value_sum_(V)           mln::trait::value_< V >::sum
# define mln_sum(V)  mln_trait_value_sum(V)
# define mln_sum_(V) mln_trait_value_sum_(V)

# define mln_trait_value_name(V)         mln::trait::value_< V >::name()

# define mln_value_quant_from_(C)                                       \
  mlc_if(mln::metal::bool_<( int(C) > int(mlc_pow_int(2, mln::def::low_quant_nbits)) \
                             || int(C) == 0                             \
                             || int(C) == -1)>,                         \
         mln::trait::value::quant::high,                                \
         mln::trait::value::quant::low)


// 
// Technical note:
// This macro might seem weird, yet it is NOT.  We have to change the value
// of N, even when N is less than the low quant threshold, because otherwise
// the call to mlc_pow_int would lead to compilation errors.
# define mln_value_card_from_(N)                \
  (int(N) <= int(mln::def::low_quant_nbits)     \
   ? mlc_pow_int((N <= 16 ? 2 : 1),             \
                 (N <= 16 ? N : 1))             \
   : 0)



namespace mln
{

  namespace trait
  {


    struct undefined_value_
    {
      typedef undef nature;
      typedef undef kind;
      typedef undef quant;

      /*
       * enum {
       *   dim = ?
       *   nbits = ?,
       *   card  = ?
       * };
       *
       * static const E min();
       * static const E max();
       * static const E epsilon();
       */

      typedef undef sum;
      // FIXME: signed or not, with zero or not, centered or not, etc.
    };


    struct default_value_ : undefined_value_
    {
      enum {
        dim = 0,
        nbits = 0,
        card = 0
      };

      typedef trait::value::nature::unknown nature;
      typedef trait::value::kind::data      kind;
      typedef trait::value::quant::high     quant;

      /*
       * typedef ? comp_0;
       * typedef ? comp_1;
       * ...
       */
    };


    template <typename V>
    struct value_ : default_value_
    {
    };


  } // end of namespace mln::trait

} // end of namespace mln


# include <mln/trait/value/print.hh>


#endif // ! MLN_TRAIT_VALUE__HH