weak_pointer.hpp

#ifndef SRC_INC_WEAK_POINTER_HPP
#define SRC_INC_WEAK_POINTER_HPP

#include <gc++.hpp>
#include <stdexcept>

namespace GCpp
{

class bad_weak_pointer : public std::runtime_error
{
    public:
        bad_weak_pointer ()
        : std::runtime_error ("bad weak pointer")
        {}
};

template <class T>
class weak_ptr
{
    private:
        void* f_storage;
        
    public:
        explicit weak_ptr (gc_ptr<T>& p_item)
        : f_storage (p_item.storage ())
        {}
        
        operator gc_ptr<T> () const
        {
            if (not allocator_for_type<T>()->confirm (f_storage))
                throw bad_weak_pointer ();
            
            return gc_ptr<T> ((T*)f_storage);
        }
};

} // namespace GCpp

#endif /* SRC_INC_WEAK_POINTER_HPP */

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