PartialMap.h

Go to the documentation of this file.

/***************************************************************************
 *
 * Copyright (C) 2009-2010 Cassio Neri Moreira
 *
 * This file is part of the KeyValue library.
 *
 * The KeyValue library 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.
 *
 * The KeyValue library 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 KeyValue. If not, see <http://www.gnu.org/licenses/>.
 *
 **************************************************************************/

#ifndef KEYVALUE_KEY_MAP_PARTIALMAP_H_
#define KEYVALUE_KEY_MAP_PARTIALMAP_H_

#include <boost/static_assert.hpp>
#include <boost/type_traits/is_same.hpp>

#include "keyvalue/extern/String.h"
#include "keyvalue/extern/Ptime.h"
#include "keyvalue/key/Key.h"

namespace keyvalue {

// Forward declaration

namespace value {
class Variant;
}

namespace key {

template <typename OutputType>
class PartialMap {

public:

  typedef OutputType OutputType_;

  PartialMap();

  OutputType
  map(const value::Variant& variant) const;

  virtual OutputType
  get(const string& name) const = 0;

private:

  virtual string
  getName() const = 0;

  typedef typename boost::is_same<OutputType, double>::type IsDouble_;
  typedef typename boost::is_same<OutputType, ptime>::type IsPtime_;
  typedef typename boost::is_same<OutputType, unsigned int>::type IsUInt_;

  /*
   ATTENTION: If you get a compiler error here about

   'boost::STATIC_ASSERTION_FAILURE<x>'

   this means that you are trying to instantiate PartialMap policy for an
   OutputType different of double, ptime and unsigned int.
   */
  BOOST_STATIC_ASSERT(IsDouble_::value || IsPtime_::value ||
    IsUInt_::value);

}; // class PartialMap

} // namespace key
} // namespace keyvalue

#endif // KEYVALUE_KEY_MAP_PARTIALMAP_H_