b.hh

Go to the documentation of this file.

#ifndef VCSN_WEIGHTSET_B_HH
# define VCSN_WEIGHTSET_B_HH

# include <cassert>
# include <ostream>
# include <string>

# include <vcsn/core/join.hh>
# include <vcsn/misc/escape.hh>
# include <vcsn/misc/hash.hh>
# include <vcsn/misc/raise.hh>
# include <vcsn/misc/stream.hh>
# include <vcsn/misc/star_status.hh>
# include <vcsn/weightset/fwd.hh>
# include <vcsn/weightset/weightset.hh>

namespace vcsn
{
  namespace detail
  {
  class b_impl
  {
  public:
    using self_type = b;

    static std::string sname()
    {
      return "b";
    }

    std::string vname(bool = true) const
    {
      return sname();
    }

    static b make(std::istream& is)
    {
      eat(is, sname());
      return {};
    }

    using value_t = bool;

    static value_t
    zero()
    {
      return false;
    }

    static value_t
    one()
    {
      return true;
    }

    static value_t
    add(const value_t l, const value_t r)
    {
      return l || r;
    }

    static value_t
    mul(const value_t l, const value_t r)
    {
      return l && r;
    }

    static value_t
    rdiv(const value_t l, const value_t r)
    {
      require(!is_zero(r), "div: division by zero");
      return l;
    }

    static value_t
    ldiv(const value_t l, const value_t r)
    {
      return rdiv(r, l);
    }

    static value_t
    star(const value_t)
    {
      return one();
    }

    static bool
    equals(const value_t l, const value_t r)
    {
      return l == r;
    }

    static bool less_than(value_t lhs, value_t rhs)
    {
      return lhs < rhs;
    }

    constexpr static bool is_special(value_t)
    {
      return false;
    }

    static bool
    is_zero(const value_t v)
    {
      return !v;
    }

    static bool
    is_one(const value_t v)
    {
      return v;
    }

    static constexpr bool is_commutative() { return true; }
    static constexpr bool is_idempotent() { return true; }

    static constexpr bool show_one() { return false; }
    static constexpr star_status_t star_status()
    {
      return star_status_t::STARRABLE;
    }

    static value_t
    transpose(const value_t v)
    {
      return v;
    }

    static size_t hash(value_t v)
    {
      return hash_value(v);
    }

    static value_t
    conv(self_type, value_t v)
    {
      return v;
    }

    static value_t
    conv(std::istream& is)
    {
      int i;
      if (is >> i)
        {
          if (i == 0 || i == 1)
            return i;
          else
            fail_reading(is,
                         sname() + ": invalid value: " + std::to_string(i));
        }
      else
        fail_reading(is, sname() + ": invalid value");
    }

    static std::ostream&
    print(const value_t v, std::ostream& o,
          symbol format = symbol{"text"})
    {
      if (format == "latex")
        o << (v ? "\\top" : "\\bot");
      else
        o << (v ? '1' : '0');
      return o;
    }

    std::ostream&
    print_set(std::ostream& o, symbol format = symbol{"text"}) const
    {
      if (format == "latex")
        o << "\\mathbb{B}";
      else if (format == "text")
        o << vname();
      else
        raise("invalid format: ", format);
      return o;
    }
  };

    /*-------.
    | join.  |
    `-------*/

    VCSN_JOIN_SIMPLE(b, b);
  } // detail::

}
#endif // !VCSN_WEIGHTSET_B_HH