weak_ptr_factory

Minimalistic weak_ptr_factory class inspired by Chromium's base::WeakPtrFactory (require C++11).

This small project was made as an exercise and for fun. Its practical usage is at least debatable.

How to use

Just include weak/weak_ptr_factory.hpp or weak/weak_ptr_factory.hpp header. Classes will be available as weak::weak_ptr and weak::weak_ptr_factory.

If you want to use boost's implementations instead of C++11 std ones use:

#define WEAK_PTR_TOOLS_USE_BOOST
#include "weak_ptr_factory.hpp"

Then it will be available under weak::weak_ptr_factory.

Example

using weak::weak_ptr;
using weak::weak_ptr_factory;

class Test {
  weak_ptr_factory<Test> weak_ptr_factory_;

public:
  explicit Test() :
    weak_ptr_factory_(this)
    {}

  weak_ptr<Test> get_weak_ptr() const {
    return weak_ptr_factory_.get_weak_ptr();
  }

  void invalidate_all_ptrs() {
    weak_ptr_factory_.invalidate_all_ptrs();
  }
};

Factory is initiated with this and will create weak_ptrs to its owner with get_weak_ptr() method. On object's destruction all weak_ptrs will be invalidated.

Problems

On multithreaded environment one must be careful - since we assume that owner of a factory manages its lifetime on its own. So it should be used only when we have certainty that object cannot commit suicide between checking weak_ptr and calling the object.