Re: If a class has a virtual destructor
* HumbleWorker, quoting Bob Hairgrove:
I had to:
(1) comment out #include "stdafx.h";
(2) change the non-standard "_tmain" to plain "main";
(3) change the non-standard "_TCHAR" to "char" (better yet, just
delete the arguments to main() entirely since they are not used;
COMMENTS OF HW: My code was compiled for VS 2005 C++ Express Edition,
so that stuff was in that context.
Dear Humble Worker, first, please attribute your quotes, that is, state
whom you are quoting.
Please just ask if the rationale for that is unclear, but please do it
anyway.
OK, now, as to the code, there's no need for these non-standard features.
Consider: your code is so much greater & impressive expressed in
standard C++!
Also, it then reaches a much wider audience, avoids comments like those
you quoted unattributed, and avoids the article being rejected for being
(needlessly) environment specific, as at least one moderator would
probably have done. ;-)
(4) take the definition of CDerived<T> and bRet out of the body of
the function HasVirtualDtor<T> and make them global;
Only then I was able to compile and run it. :(
COMMENTS OF HW: If you take them out of the function body, the whole
point of having a single template function for testing the virtual d-
tor would be gone.
No, simply make it a template class, but...
The function SHOULD compile on any compiler. It
compiles on MSVC compliler.
Yeah.
But, it's not guaranteed to do anything sensible, because in the case
where the class T to be tested has non-virtual destructor, deleting a
Derived via a pointer to T has formally Undefined Behavior.
That academic problem aside, creating an instance of the class is a very
expensive way to test for virtual destructor, may have undesired side
effects, and doesn't help at compile time, which presumably is where
this functionality is required.
Cheers,
- Alf
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