Destructors and exceptions

Christos TZOTZIOY Georgiou tzot at sil-tec.gr
Tue Jun 8 11:19:15 CEST 2004


On 7 Jun 2004 07:51:23 -0700, rumours say that dkturner at telkomsa.net
(David Turner) might have written:

>Hi all
>
>I noticed something interesting while testing some RAII concepts
>ported from C++ in Python.  I haven't managed to find any information
>about it on the web, hence this post.
>
>The problem is that when an exception is raised, the destruction of
>locals appears to be deferred to program exit.  Am I missing
>something?  Is this behaviour by design?  If so, is there any reason
>for it?  The only rationale I can think of is to speed up exception
>handling; but as this approach breaks many safe programming idioms, I
>see it as a poor trade.

[snip code]

ISTR that when an exception is raised, there is a reference to the code
frame (and therefore to its locals) kept somewhere; you can access this
info through the sys.exc_info call.  Have you tried running
sys.exc_clear after the exception was raised?

Apart from that, advice from others not to rely on finalisation of
objects to clean up still applies.
-- 
TZOTZIOY, I speak England very best,
"I have a cunning plan, m'lord" --Sean Bean as Odysseus/Ulysses



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