Re: [boost] Boost super_string

From: Martin Bonner (martin.bonner_at_[hidden])
Date: 2006-10-13 04:34:22

----Original Message----
From: boost-bounces_at_[hidden]
[mailto:boost-bounces_at_[hidden]] On Behalf Of Caleb Epstein Sent:
12 October 2006 22:09 To: boost_at_[hidden]
Subject: Re: [boost] Boost super_string

> On 10/12/06, Arkadiy Vertleyb <vertleyb_at_[hidden]> wrote:
> 
>> More importantly, according
>> to the standard, the basic_string class destructor is not virtual,
>> and so basic_string is not intended for derivation.
> 
> Wouldn't this only matter if super_string added data members (it
> doesn't AFAICT)
Not relevent.

> and was being deleted via pointers to
> std::basic_string?

THIS is the relevent point.

   string* pstr = new super_string;
   delete pstr;

is undefined behaviour.  In practise, you get away with it if
super_string doesnt do anything in its destructor, and if all additional
members don't do anything in their destructors.  However, formally it is
ALWAYS undefined behaviour.

The real question is how often will people create a super_string on the
heap, and delete it through pointer to string.

-- 
Martin Bonner
Martin.Bonner_at_[hidden]
Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB24 6WZ,
ENGLAND Tel: [phone]