repeat.hh

// This file is a part of Aurelia.
// Copyright (C) 2010  Valentin David
// Copyright (C) 2010  University of Bergen
//
// 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 3 of the License, or
// (at your option) any later version.
//
// This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
#ifndef __REPEAT_HH
# define __REPEAT_HH

# include "../strategies.hh"

namespace aurelia {

  template <typename S>
  struct repeat_strategy {
  private:
    S s;
  public:
    repeat_strategy(const S& s): s(s) {}
    repeat_strategy(const repeat_strategy& o): s(o.s) {}

    //FIXME: we must check that S is T -> T
    template <typename T>
    T operator()(T t) const {
      while (true) {
        try {
          t = s(t);
        } catch (failure) {
          return t;
        }
      }
    }
  };

  template <typename S>
  repeat_strategy<S> repeat(const S& s) {
    return repeat_strategy<S>(s);
  }

}

#endif