Blender
V3.3
|
Simple RAII wrappers for std:: sequential containers. More...
#include <algorithm>
Go to the source code of this file.
Classes | |
class | Freestyle::PointerSequence< C, T > |
Namespaces | |
Freestyle | |
inherits from class Rep | |
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.
Definition in file PointerSequence.h.