Re: Equivalent of dynamic_cast (downcast) for tagged types

["J-P. Rosen" <rosen@adalog.fr>]

Le 27/01/2011 17:18, Dmitry A. Kazakov a �crit :
>    if X'Tag = T'Tag then -- X is of T
>       Do_Something (T (X));  -- No dispatch
>    end if;
> 
or
    if X in T then -- slightly more elegant

>> If you say that I should not do this because it is not good practice,
It's bad practice in C++ because it is unsafe.
I see no objection in Ada, where tags are checked, and I have some
pretty convincing examples of that.

Admitedly, it not very OOrthodox, but OOrthodoxy has been defined by C++
people!


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