sharedReference.hpp

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#ifndef _Wolframe_SHARED_REFERENCE_HPP_INCLUDED
#define _Wolframe_SHARED_REFERENCE_HPP_INCLUDED

#include <cstddef>
#include <boost/shared_ptr.hpp>

namespace _Wolframe {
namespace types {

template <class OBJ>
class SharedReference
{
public:
        struct Pointer
        {
                OBJ* m_ptr;     

                explicit Pointer( OBJ* ptr_=0)
                        :m_ptr(ptr_){}
                ~Pointer()
                {
                        if (m_ptr) delete m_ptr;
                }
        };

        SharedReference( const SharedReference& o)
                :m_ref(o.m_ref){}

        SharedReference( OBJ* ptr=0)
                :m_ref(boost::shared_ptr<Pointer>( new Pointer( ptr))){}

        virtual ~SharedReference(){}

        SharedReference& operator =( const SharedReference& o)
        {
                m_ref = o.m_ref;
                return *this;
        }

        OBJ* get() const
        {
                return m_ref->m_ptr;
        }

        void reset( OBJ* ptr=0)
        {
                if (m_ref->m_ptr && m_ref->m_ptr != ptr) delete m_ref->m_ptr;
                m_ref->m_ptr = ptr;
        }

        OBJ* operator -> () const
        {
                return m_ref->m_ptr;
        }

        OBJ& operator *() const
        {
                return *m_ref->m_ptr;
        }

private:
        boost::shared_ptr<Pointer> m_ref;       
};

}}//namespace
#endif