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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Structured exception information
Date: Sat, 20 Jan 2007 17:07:18 -0500
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Date: 2007-01-20T17:07:18-05:00
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Stephen Leake <stephen_leake@stephe-leake.org> writes:

> I'm certainly not willing to give up any of Ada's other features to
> get it.

I think there's no need to give up anything.

>>> If you look into the details of "structured exception handling" in
>>> other languages and implementations, they have bugs, and fundamental
>>> flaws in design.
>>
>> Please be more specific.
>
> Well, I can't. I plead guilty to arguing from authority and vague
> memory on this one. The memory is of discussions of problems with
> various exception implementations in C++ and Java, on other
> newsgroups. 

OK, fair enough.

Here's my vague memory:

C++ always had finalization (destructors).  Later on, exceptions were
added.  There was much moaning and gnashing of teeth from implementers,
claiming "exceptions are hard to implement properly".

Ada always had exceptions.  Later on, finalization was added.  There
was much moaning and gnashing of teeth from implementers, claiming
"finalization is hard to implement properly".

The truth is, the interactions between exceptions and finalization are
nasty, and hard to get right.

- Bob