krat_exp_pattern.hh

// krat_exp_pattern.hh: this file is part of the Vaucanson project.
//
// Vaucanson, a generic library for finite state machines.
//
// Copyright (C) 2001, 2002, 2003, 2004 The Vaucanson Group.
//
// This program 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; either version 2
// of the License, or (at your option) any later version.
//
// The complete GNU General Public Licence Notice can be found as the
// `COPYING' file in the root directory.
//
// The Vaucanson Group consists of people listed in the `AUTHORS' file.
//
#ifndef VCSN_ALGEBRA_IMPLEMENTATION_SERIES_KRAT_EXP_PATTERN_HH
# define VCSN_ALGEBRA_IMPLEMENTATION_SERIES_KRAT_EXP_PATTERN_HH

# include <vaucanson/design_pattern/element.hh>
# include <vaucanson/algebra/implementation/series/series.hh>
# include <vaucanson/algebra/implementation/series/rat/dispatch_visitor.hh>

namespace vcsn {

  namespace algebra {

    /*---------.
    | BinaryOp |
    `---------*/

    template <class T, class U>
    struct BinaryOp
    {
      typedef T lhs_node_type;
      typedef U rhs_node_type;

      BinaryOp();
      BinaryOp(const BinaryOp& b);
      BinaryOp(const T& lhs, const U& rhs);
      T&                lhs();
      const T&          lhs() const;
      U&                rhs();
      const U&          rhs() const;

    private:
      T lhs_;
      U rhs_;
    };

    /*--------.
    | UnaryOp |
    `--------*/

    template <class T>
    struct UnaryOp
    {
      typedef T value_type;

      UnaryOp();
      UnaryOp(const UnaryOp& b);
      UnaryOp(const T& node);
      T&                value();
      const T&          value() const;

    private:
      T node_;
    };

    /*------.
    | Value |
    `------*/

    template <class T>
    struct Value
    {
      typedef T value_type;

      Value();
      Value(const Value& v);
      Value(const T& v);
      const T&  value() const;
      T&        value();

    private:
      T v_;
    };

    /*---------------.
    | GenericMatcher |
    `---------------*/

    template <class Self, class T, class U, class F>
    struct GenericMatcher
    {
      typedef U return_type;

      U
      match(const T& ast);

    protected:
      GenericMatcher();
    };

#define DecBinaryOp(N, T, U)                                    \
struct N     : public vcsn::algebra::BinaryOp<T, U>             \
{                                                               \
  N(const T& lhs, const U& rhs) : vcsn::algebra::BinaryOp<T, U>(lhs, rhs) \
  {}                                                            \
};

#define DecUnaryOp(N, T)                                \
struct N     : public vcsn::algebra::UnaryOp<T>         \
{                                                       \
  N(const T& node) : vcsn::algebra::UnaryOp<T>(node)    \
  {}                                                    \
};

#define DecLeaf(N, U)                           \
  struct N : public vcsn::algebra::Value<U>     \
  {                                             \
    N(const U& v) :                             \
      vcsn::algebra::Value<U>(v)                \
    {}                                          \
  };

#define DecFinalLeaf(N)                         \
  struct N                                      \
  {                                             \
    N()                                         \
    {}                                          \
  };

#define MATCH__(N, Lhs, Rhs)                    \
return_type                                     \
match_node##N(const N& p____)           \
{                                               \
  typename N::lhs_node_type Lhs = p____.lhs();  \
  typename N::rhs_node_type Rhs = p____.rhs();

#define MATCH_(N, Val)                          \
return_type                                     \
match_node##N(const N& p____)           \
{                                               \
  typename N::value_type Val(p____.value());

#define MATCH(N)                                        \
return_type                                             \
match_node##N(const N&)                         \
{

#define END }


    template <class Self, class T, class U, class F>
    struct KRatExpMatcher : public GenericMatcher<Self, T, U, F>
    {
      typedef U                          return_type;
      typedef typename T::semiring_elt_value_t semiring_elt_value_t;
      typedef typename T::monoid_elt_value_t monoid_elt_value_t;

      DecBinaryOp(Product, T, T);
      DecBinaryOp(Sum, T, T);
      DecUnaryOp(Star, T);
      DecBinaryOp(LeftWeight, semiring_elt_value_t, T);
      DecBinaryOp(RightWeight, T, semiring_elt_value_t);
      DecLeaf(Constant, monoid_elt_value_t);
      DecFinalLeaf(One);
      DecFinalLeaf(Zero);

    protected:
      KRatExpMatcher() {}
    };

#define INHERIT_CONSTRUCTORS(Self, T, U, F) \
   typedef ::vcsn::algebra::KRatExpMatcher<Self, T, U, F> krat_exp_matcher_t; \
   typedef typename krat_exp_matcher_t::Product         Product;             \
   typedef typename krat_exp_matcher_t::Sum             Sum;                \
   typedef typename krat_exp_matcher_t::Star            Star;                \
   typedef typename krat_exp_matcher_t::LeftWeight      LeftWeight;          \
   typedef typename krat_exp_matcher_t::RightWeight     RightWeight;         \
   typedef typename krat_exp_matcher_t::Constant        Constant;            \
   typedef typename krat_exp_matcher_t::One             One;                 \
   typedef typename krat_exp_matcher_t::Zero            Zero;

      template <class Self, class Series, class T, class Dispatch>
        struct KRatExpIdentity : vcsn::algebra::KRatExpMatcher<
        Self,
        T,
        Element<Series, T>,
        Dispatch
        >
        {
          typedef Self                                      self_t;
          typedef Element<Series, T>                        return_type;
          typedef typename Element<Series, T>::semiring_elt_t     semiring_elt_t;
          typedef typename semiring_elt_t::value_t                  semiring_elt_value_t;
          typedef typename Element<Series, T>::monoid_elt_t monoid_elt_t;
          typedef typename monoid_elt_t::set_t              monoid_t;
          typedef typename monoid_t::alphabet_t             alphabet_t;
          typedef typename alphabet_t::letter_t             letter_t;
          INHERIT_CONSTRUCTORS(self_t, T, semiring_elt_t, Dispatch);

          KRatExpIdentity(const Element<Series, T>& exp) :
            exp_(exp)
          {}

          MATCH__(Product, lhs, rhs)
          {
            return match(lhs) * match(rhs);
          }
          END

          MATCH__(Sum, lhs, rhs)
          {
            return match(lhs) + match(rhs);
          }
          END

          MATCH_(Star, e)
          {
            return_type r (match(e));
            r.star();
            return r;
          }
          END

          MATCH__(LeftWeight, w, e)
          {
            semiring_elt_t welt (exp_.structure().semiring(), w);
            return  welt * match(e);
          }
          END

          MATCH__(RightWeight, e, w)
          {
            semiring_elt_t welt (exp_.structure().semiring(), w);
            return match(e) * welt;
          }
          END

          MATCH_(Constant, m)
          {
            monoid_elt_t melt (exp_.structure().monoid(), m);
            return Element<Series, T> (exp_.structure(), melt);
          }
          END

          MATCH(Zero)
          {
            return zero_as<T>::of(exp_.structure());
          }
          END

          MATCH(One)
          {
            return identity_as<T>::of(exp_.structure());
          }
          END

        protected:
          Element<Series, T>  exp_;
        };


    } // algebra

} // vcsn

# ifndef VCSN_USE_INTERFACE_ONLY
#  include <vaucanson/algebra/implementation/series/krat_exp_pattern.hxx>
# endif // VCSN_USE_INTERFACE_ONLY

#endif // ! VCSN_ALGEBRA_IMPLEMENTATION_SERIES_KRAT_EXP_PATTERN_HH

---