Re: STL non virtual DTOR

From:
"James Kanze" <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Sat, 24 Feb 2007 11:31:35 CST
Message-ID:
<1172318167.260877.232830@p10g2000cwp.googlegroups.com>
W. J. La Cholter wrote:

"Sushrut Sardeshmukh" <bestbrain@gmail.com> wrote in
news:1172132440.361603.82270@p10g2000cwp.googlegroups.com:

Why did STL designer chose not to make std:list DTOR virtual.
making its DTOR virtual will make our life easier, isn't it?

Also..
In which case I should do this and which case I should not.

class my_generic_list:: public std::list
{
//my code
}


You'll find that there are no container classes in the Standard
Library that share an inheritance hierarchy, except insofar as they
are implemented with the same representation (e.g., map and set both
use red-black trees).


Even then, it should be private inheritance, an implementation
detail.

Instead, the interfaces across containers are
similar, where all provide begin() and end() for iteration. If
anything were virtual (as a previous poster pointed out is not), then
some of the most basic functions like begin() and end() would be
virtual.


Which is, of course, a lot more flexible, and arguably a better
design.

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