Rationale behind the deprecation of __getslice__?

[Nick Coghlan]

Steven Bethard wrote:
> Carl Banks wrote:
> 
>> Wouldn't it work to have __getslice__ call __getitem__?  And, since
>> that would be too much of a performance hit, have it check whether its
>> type is list (or str or tuple), and only call __getitem__ if it is not
>> (i.e., only for subclasses).  I don't think that would be too bad.
>>
>> Subclasses would still be free to override __getslice__, but wouldn't
>> have to.
> 
> Yeah, that doesn't seem like it would be too bad.  Probably someone 
> would have to actually run some benchmarks to see what kind of 
> performance hit you get...  But it would definitely solve the OP's 
> problem...

It might be better handled at construction time - if the class supplied to 
__new__ is a subclass of the builtin type, swap the __getslice__ implementation 
for one which delegates to __getitem__.

Cheers,
Nick.


-- 
Nick Coghlan   |   ncoghlan at email.com   |   Brisbane, Australia
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