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//
// Filename : PointerSequence.h
// Author(s) : Alexander Beels
// Purpose : Class to define a cell grid surrounding
// the projected image of a scene
// Date of creation : 22/11/2010
//
///////////////////////////////////////////////////////////////////////////////
//
// Copyright (C) : Please refer to the COPYRIGHT file distributed
// with this source distribution.
//
// 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.
//
// 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, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
///////////////////////////////////////////////////////////////////////////////
//
// Simple RAII wrappers for std:: sequential containers
//
///////////////////////////////////////////////////////////////////////////////
//
// PointerSequence
//
// Produces a wrapped version of a sequence type (std::vector, std::deque, std::list)
// that will take ownership of pointers tht it stores. Those pointers will be deleted
// in its destructor.
//
// Because the contained pointers are wholly owned by the sequence, you cannot make a
// copy of the sequence. Making a copy would result in a double free.
//
// This is a no-frills class that provides no additional facilities. The user is
// responsible for managing any pointers that are removed from the list, and for making
// sure that any pointers contained in the class are not deleted elsewhere. Because
// this class does no reference counting, the user must also make sure that any pointer
// appears only once in the sequence.
//
// If more sophisticated facilities are needed, use tr1::shared_ptr or boost::shared_ptr.
// This class is only intended to allow one to eke by in projects where tr1 or boost are
// not available.
//
// Usage: The template takes two parameters, the standard container, and the class held
// in the container. This is a limitation of C++ templates, where T::iterator is not a
// type when T is a template parameter. If anyone knows a way around this
// limitation, then the second parameter can be eliminated.
//
// Example:
// PointerSequence<vector<Widget*>, Widget*> v;
// v.push_back(new Widget);
// cout << v[0] << endl; // operator[] is provided by std::vector, not by PointerSequence
// v.destroy(); // Deletes all pointers in sequence and sets them to NULL.
//
// The idiom for removing a pointer from a sequence is:
// Widget* w = v[3];
// v.erase(v.begin() + 3); // or v[3] = 0;
// The user is now responsible for disposing of w properly.
//
///////////////////////////////////////////////////////////////////////////////
#ifndef POINTERSEQUENCE_H
# define POINTERSEQUENCE_H
#include <algorithm>
template <typename C, typename T>
class PointerSequence : public C {
PointerSequence (PointerSequence& other);
PointerSequence& operator= (PointerSequence& other);
static void destroyer (T t) {
delete t;
}
public:
PointerSequence () {};
~PointerSequence () {
destroy();
}
void destroy () {
for_each (this->begin(), this->end(), destroyer);
}
};
#endif // POINTERSEQUENCE_H
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