Re: Exception Misconceptions: Exceptions are for unrecoverable errors.

From:

tanix@mongo.net (tanix)

Newsgroups:

comp.lang.c++

Date:

Sat, 26 Dec 2009 13:22:06 GMT

Message-ID:

<hh52lu$8rc$6@news.eternal-september.org>

In article <bb09f18f-ce17-48b8-923d-5f72cd5bfefa@d20g2000yqh.googlegroups.com>, peter koch <peter.koch.larsen@gmail.com> wrote:

On 24 Dec., 12:01, ta...@mongo.net (tanix) wrote:

In article

<e5f9f274-0663-4563-bc4d-feaa1d858...@e27g2000yqd.googlegroups.com>, peter
koch <peter.koch.lar...@gmail.com> wrote:

On 23 Dec., 23:51, Kaz Kylheku <kkylh...@gmail.com> wrote:

On 2009-12-22, James Kanze <james.ka...@gmail.com> wrote:

And there can be other issues besides leaking. In the end,
you've got to ensure internal consistency for all possible
control flows. When some of the possible control flows are the
result of an exception, then this requirement is called
exception safety.

Right; for instance failing to unlock a mutex, or roll
back a transaction, aren't resource leaks.

Yes it is. A mutex held is also a ressource, and so is a transaction.
Both should be wrapped in a class having appropriate destructor
semantics.

Yup.

You have to unwind EVERYTHING, no matter how small it is.
Otherwise, sooner or later your box will run out of steam.

You have to unwind everything in any language. By unwinding it in the
destructor you only write it once

Looks nice on paper. I agree.

and you dont have to have have
special code for exceptions.

Huh?

Contrast this to Java: here you need the
code explicitly present in every function using the feature.

Sorry. I don't follow this.

/Peter

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