Re: query on dynamic cast

On Apr 30, 6:56 pm, Bharath <tiromarc...@[EMAIL PROTECTED]
> wrote:
> [...]
> class CBase
> {
>      void dummy() {}
> };
>
> class CDerived: public CBase
> { };
>
> int main () {
>    try {
>      CBase * pba = new CDerived;
>      CDerived * pd;
>
>      pd = dynamic_cast<CDerived*>(pba);
>      if (pd==0) cout << "Null pointer on first type-cast" << endl;
>    } catch (exception& e) {cout << "Exception: " << e.what();}
>    return 0;
> }

( presumably, the problem was that the "Null pointer on first type-
cast" message was being printed unexpectedly )

RTTI is a mechanism sup****ting cl***** employing virtual dispatch.
Just make a member of CBase virtual (even dummy() will do), and the
dynamic_cast<> will start working.

Cheers, Tony

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