Re: [boost] Is there any interest in a library that provides containers with virtual destructors?

From: Matt Calabrese (rivorus_at_[hidden])
Date: 2005-10-26 22:52:18

On 10/26/05, Victor A. Wagner Jr. <vawjr_at_[hidden]> wrote:

> perhaps some other paragraph? this doesn't address anything about
> derived objects.

Just look 2 paragraphs further:

5.3.5 paragraph 3

"In the first alternative (delete object), if the static type of the operand
is different from its dynamic type, the static type shall be a base class of
the operand's dynamic type and the static type shall have a virtual
destructor or the behavior is undefined." ...

The paragraph then goes further to talk about arrays.

As for interest in the STL containers with virtual destructors, I'd
personally say no. I've never encountered a situation where it would be
useful or at least useful and better than other alternatives. Anyway, the
desire for a virtual destructor could exist with any type. If someone wants
virtual destructors for STL containers, then what next? multi_array with
virtual destructors? graphs? Forgive me if that sounds like a slippery slope
argument, but really I see no logic as to why one would want virtual
destructors for STL containers yet not any other types. You can use the same
type of argument for any type you can think of -- "I want to derive from the
type and then add functionality, but want to delete it via a pointer to the
base class". Does this mean that all types should have one version with
virtual destructors, and one without? Definately not. I just don't see why
someone would want to make the exception for STL containers.

--
-Matt Calabrese