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/*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#pragma once
/** \file
* \ingroup freestyle
* \brief 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 that 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.
*/
#include <algorithm>
#ifdef WITH_CXX_GUARDEDALLOC
# include "MEM_guardedalloc.h"
#endif
namespace Freestyle {
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);
}
#ifdef WITH_CXX_GUARDEDALLOC
MEM_CXX_CLASS_ALLOC_FUNCS("Freestyle:PointerSequence")
#endif
};
} /* namespace Freestyle */
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