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Python style guidelines

From: John Roth <news...@jhrothjr.com>
Thu, 11 Mar 2004 12:16:54 -0500
"Peter Hansen" <peter at engcorp.com> wrote in message
news:EO%3c.2675$G3.20988 at localhost...
> Josef Meile wrote:> >>>>>> a='test'> >>>>>> if a.find('foo'):> >>>> >>>> >>> ...    print "foo was found"> >>> ...> >>> foo was found> >>> >>> >>> >> a.find does not return a boolean, so that particular style guideline> >> does not apply.> >> > I know, but I found this on the Zope source, which> > means that there is people thinking that the False> > on python includes negative values.>> I believe it's more likely they just forgot what find() did return, as> they were writing the code.  I've done the same, thinking it was a> boolean, not thinking that it returned a negative but that negatives> were considered false.

I suspect that's a rather common error. I'd much prefer
that both find and index return an object that acted like
a number but returned the logically correct response when
queried as a boolean: true for zero and false for -1. Also,
the "not found" object should throw an exception if it's
used as an index or slice.

John Roth
>> -Peter

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