[Quantlib-dev] Handle class conversion. Open discussion.

[Kakhkhor A. <kab...@gm...>]

Dear all,
Current implementation of Handle class doesn't permit conversion from
Handle<Derived> to Handle<Base>. If we supply Handle<Base> with
converting constructor, an instance of Handle<Derived> could be
substituted where an instance of Handle<Base> is expected. For
example, an instance of Handle<SimpleQuote> could be passed  to term
structure constructors instead of Handle<Quote> instance. This
conversion makes sense, since SimpleQuote is a subtype of Quote.

Enabling conversion would allow user code use derived class features
without a need for dynamic casting. Safety of conversion can be
checked at runtime, similar to pointer down-casting.

I did some coding in this direction and so far everything looks OK.
Since it is a design decision and not a bug fix, I wanted to know what
other think before submitting my code.

Regards,
Kakhkhor Abdijalilov.