Option.h

Go to the documentation of this file.

// -*- C++ -*-4 1999/10/29 20:41:34 dugas

// PLearn (A C++ Machine Learning Library)
// Copyright (C) 1998 Pascal Vincent
// Copyright (C) 1999-2002 Pascal Vincent, Yoshua Bengio and University of Montreal
// Copyright (C) 2002 Frederic Morin

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// 
//  1. Redistributions of source code must retain the above copyright
//     notice, this list of conditions and the following disclaimer.
// 
//  2. Redistributions in binary form must reproduce the above copyright
//     notice, this list of conditions and the following disclaimer in the
//     documentation and/or other materials provided with the distribution.
// 
//  3. The name of the authors may not be used to endorse or promote
//     products derived from this software without specific prior written
//     permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
// NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// 
// This file is part of the PLearn library. For more information on the PLearn
// library, go to the PLearn Web site at www.plearn.org



/* *******************************************************      
   * $Id: Option.h,v 1.5 2004/06/26 00:24:12 plearner Exp $
   * This file is part of the PLearn library.
   ******************************************************* */


#ifndef Option_INC
#define Option_INC

#include "OptionBase.h"

namespace PLearn {
using namespace std;

template<class ObjectType, class OptionType, class ConstOptionType>
class Option: public OptionBase
{
protected:
  OptionType ObjectType::*ptr;

public:

  Option(const string& optionname, OptionType ObjectType::* member_ptr, 
         flag_t flags, const string& optiontype, const string& defaultval,
         const string& description)
    :OptionBase(optionname, flags, optiontype, defaultval, description),
    ptr(member_ptr) {}
  virtual void read(Object* o, PStream& in) const
  { in >> dynamic_cast<ObjectType*>(o)->*ptr; }
  virtual void read_and_discard(PStream& in) const
  { 
    string dummy;
    in.smartReadUntilNext(";)", dummy);
    in.unget();
    //OptionType op; //dummy object that will be destroyed after read
    //in >> op; //read dummy object
  }
  virtual void write(const Object* o, PStream& out) const
  { out << static_cast<ConstOptionType>(dynamic_cast<const ObjectType *>(o)->*ptr); }

  virtual Object* getAsObject(Object* o) const
  { return toObjectPtr(dynamic_cast<ObjectType*>(o)->*ptr); }

  virtual const Object* getAsObject(const Object* o) const
  { return toObjectPtr(dynamic_cast<const ObjectType*>(o)->*ptr); }

  virtual Object *getIndexedObject(Object *o, int i) const
  { return toIndexedObjectPtr(dynamic_cast<ObjectType*>(o)->*ptr, i); };

  virtual const Object* getIndexedObject(const Object *o, int i) const
  { return toIndexedObjectPtr(dynamic_cast<const ObjectType*>(o)->*ptr, i); };

  virtual string optionHolderClassName(const Object* o) const
  { return dynamic_cast<const ObjectType*>(o)->ObjectType::classname(); }
};



template<class ObjectType, class OptionType>
inline void declareOption(OptionList& ol,                      
                          const string& optionname,            
                          OptionType ObjectType::* member_ptr, 
                          OptionBase::flag_t flags,            
                          const string& description,           
                          const string & defaultval="")        
{ ol.push_back(new Option<ObjectType, OptionType, const OptionType>(optionname, member_ptr, flags, 
                                                                    TypeTraits<OptionType>::name(), 
                                                                    defaultval, description)); }
template<class ObjectType, class OptionType>
inline void declareOption(OptionList& ol, const string& optionname, OptionType *ObjectType::* member_ptr, OptionBase::flag_t flags,
                          const string& description, const string & defaultval="")
{ ol.push_back(new Option<ObjectType, OptionType *, const OptionType *>(optionname, member_ptr, flags, TypeTraits<OptionType *>::name(), 
                                                                        defaultval, description)); }
      
template<class ObjectType, class OptionType>
inline void redeclareOption(OptionList& ol,                      
                            const string& optionname,            
                            OptionType ObjectType::* member_ptr, 
                            OptionBase::flag_t flags,            
                            const string& description,           
                            const string & defaultval="")        
{
  bool found = false;
  for (OptionList::iterator it = ol.begin(); !found && it != ol.end(); it++) {
    if ((*it)->optionname() == optionname) {
      // We found the option to redeclare.
      found = true;
      (*it) = new Option<ObjectType, OptionType, const OptionType>
        (optionname, member_ptr, flags, TypeTraits<OptionType>::name(), defaultval, description);
    }
  }
  if (!found) {
    // We tried to redeclare an option that wasn't declared previously.
    PLERROR("In Option::redeclareOption - The option you are trying to redeclare has not been declared yet.");
  }
}


} // end of namespace PLearn

#endif 

---