Returning None from methods that mutate object state
17 May
2014
17 May
'14
8:14 a.m.
During a conversation today, I realised that the convention of returning None from methods that change an object's state isn't captured the Programming Recommendations section of PEP 8. Specifically, I'm referring to this behaviour:
[].sort() is None True "ABC".lower() is None False
That's a deliberate design choice, and one that has been explained a few times on the list when folks ask why "[].sort().reverse()" doesn't work when "'ABC'.lower().replace('-', '_')" does. Would it be worth adding such a note? Or is it out of scope? Cheers, Nick. -- Nick Coghlan | ncoghlan@gmail.com | Brisbane, Australia
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participants (10)
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Antoine Pitrou -
Chris Barker -
Greg Ewing -
Guido van Rossum -
Hrvoje Niksic -
Nathaniel Smith -
Nick Coghlan -
R. David Murray -
Steven D'Aprano -
Terry Reedy