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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Question about OO programming in Ada
Date: 28 Nov 2003 06:37:18 +0000
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Date: 2003-11-28T06:37:18+00:00
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"Robert I. Eachus" <rieachus@comcast.net> writes:

> subtle memory leaks.  (The usual problem cases are when an exception
> occurs during the creation or freeing of a data structure.)

I'm not at all sure that the Booch Components at
(http://www.pushface.org/components/bc) are safe against this sort of
thing -- that is, against running out of memory while adding an
element to a container. If that is going to be a problem, I would
expect people to be using the bounded forms, which don't allocate
memory (of course, the element may be a controlled type with internal
memory management).

I would have thought that a system where an exception occurs in
manipulating data structures is almost bound to be inconsistent and
needs restarting as soon as possible. Of course if the battle override
switch is on you will carry on as best you can, but you are definitely
at risk.

I doubt you can fix this "merely" by making the containers
exception-safe. No real help having a consistent list if the data in
it is inconsistent! (but always nice to avoid walking off the end of a
list, of course).

-- 
Simon Wright                               100% Ada, no bugs.