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From: Ian Kelly <ian.g.kelly@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Try: rather than if :
Date: Mon, 14 Dec 2015 16:53:49 -0700
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On Mon, Dec 14, 2015 at 4:48 PM, Vincent Davis <vincent@vincentdavis.net> wrote:
> On Mon, Dec 14, 2015 at 4:14 PM, Cameron Simpson <cs@zip.com.au> wrote:
>
>> First, notice that the code inside the try/except _only_ fetches the
>> attribute.  Your version calls the "write" attribute, and also accesses
>> handle.name. Either of those might also emit AttributeError, and should
>> probably not be silently caught.
>>
>
> I think the intent of the original code was to check if handle had the
> attribute "name", I don't think the attribute "write" was the issue.
>
> So then possibly this based on your suggestion:
> try:
>     write = handel.write
> except AttributeError:
>     raise

Except that catching an exception just to immediately re-raise it is
silly. This would be better:

try:
    name = handle.name
except AttributeError:
    pass
else:
    handle.write("# Report_file: %s\n" % name)