On Fri, 2004-10-29 at 23:52 +0200, Andrew Bennetts wrote:
<foom> exarkun: I suspect we should introduce a UncatchableExceptions constant somewhere <foom> exarkun: and require that all except:'s are preceded by except UncatchableExceptions: raise <exarkun> foom: It's possible that is a good idea. <exarkun> foom: I'm not really sure, though. <spiv> foom: With (KeyboardInterrupt, SystemExit, MemoryError, SystemError) ? <foom> spiv: yes
I guess this would live in twisted.python somewhere, and the coding standard would be updated to require its use instead of bare "except:"
Python-dev have discussed a similar measure for the python standard library (in the exceptions module), but hadn't come to any consensus last time I looked.
Thoughts? Objections?
Not an objection *per se*, but I think it would be better to see how the debate on python-dev turns out; I am pretty sure there are a lot of subtle issues to consider. For example, I could go either way on including SystemExit in that list; there have been many times, when working with Manhole or similar, that I've imported a script that wasn't intended for use as a module and had it attempt to exit the interpreter with a sys.exit; I was glad that except: really was a catch-all in those cases. I also ponder what a Deferred with a Failure whose value is MemoryError would mean :). In general, though, I think that the Throwable/Exception distinction, as in Java, is a pretty good idea.