Noob Q: subclassing or wrapping file class
no.email at please.post
Thu Sep 17 01:06:18 CEST 2009
In <pan.2009.09.16.22.09.59 at REMOVE.THIS.cybersource.com.au> Steven D'Aprano <steven at REMOVE.THIS.cybersource.com.au> writes:
>On Wed, 16 Sep 2009 21:56:09 +0000, kj wrote:
>> I thought at first that I could achieve this by overriding __getattr__:
>> def __getattr__(self, attribute):
>> return self.fh.__getattr__(attribute)
>> But to my surprise this did not work too well. For example, if I use a
>> GzipFile object as the argument to MyFile, the iterator of the resulting
>> object works as expected, but if I attempt to access its closed
>> attribute I get the error
>> AttributeError: GzipFile instance has no attribute '__getattr__'
>> And it doesn't have __getattribute__ either. (And here I'd been
>> thinking that __getattr__ and __getattribute__ were pretty much
>> universal... Clearly not!)
>> Is there a standard idiom that I'm missing for doing this sort of thing?
This did the trick.
>Also, do a search for "automatic delegation python", or just look at Alex
>Martelli's cookbook recipe:
That was instructive. Thanks!
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