c++ - Can I make an assignment operator on a base class that returns sub-class type -

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sorry bad title... have base class like:

template<class t> class gptr { public:     typedef t basetype;      gptr& operator=(const basetype& rhs)     {         ...     } };

i want make subclassed specializations like:

class graphicptr : public gptr<graphic> { ... };

however base-class assignment operator still returns gptr<graphic> not graphicptr , it's annoying have copy-paste code in case core assignment operator functionality should change later.

is there neat way define base-class assignment operator returns type of actual class in use?

in c++, base class has no idea of it's children. may add template parameter derived class , use it.

template<class t, class derived> class gptr { public:     typedef t basetype;      derived& operator=(const basetype& rhs)     {         ...     } };

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