Re: [Python-Dev] [Python-checkins] r87445 - python/branches/py3k/Lib/numbers.py
On Fri, Dec 24, 2010 at 1:08 AM, Nick Coghlan ncogh...@gmail.com wrote: def __index__(self): - index(self) + someobject[self] return int(self) Changing the docstring to say operator.index(self) would be the clearest solution here. Agreed. Certainly someobject[self] isn't right. (There's also a question about whether __index__ should really be defaulting to int, but that's another issue...) Mark ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] [Python-checkins] r87445 - python/branches/py3k/Lib/numbers.py
Le 24/12/2010 02:08, Nick Coghlan a écrit : On Fri, Dec 24, 2010 at 4:41 AM, eric.araujo python-check...@python.org wrote: Fix small inaccuracy: there is no index function Yes, there is, it just isn't a builtin - it lives in the operator module. Defining object.__index__ with operator.index seems pretty circular to me :) http://docs.python.org/dev/reference/datamodel#object.__index__ does it, but it should be fixed IMO. The difference between __int__ and __index__ is also not clear. def __index__(self): -index(self) +someobject[self] return int(self) Changing the docstring to say operator.index(self) would be the clearest solution here. I disagree. __add__ is documented as implementing +, not operator.add. (Choosing to accept arbitrary index objects as integer equivalents is up to the object being indexed, just like interpreting slices is - a dict, for example, will never invoke __index__ methods). I honestly don’t know what the best fix is. We could copy the doc from datamodel (“called whenever Python needs an integer object (such as in slicing, or in the built-in bin(), hex() and oct() functions)”). I’ve been told on IRC to let Mark Dickison decide how to fix the docstrings in the numbers module (deleting them being of course an option: magic methods are documented in the language reference, they don’t need docstrings). Regards ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] [Python-checkins] r87445 - python/branches/py3k/Lib/numbers.py
On 12/26/2010 7:01 PM, Nick Coghlan wrote: Yes, the definition in the language reference could definitely be improved to mention the semantics first, and then reference operator.index second. Possible wording Indicates to the Python interpreter that the object is semantically equivalent to the returned integer, rather than merely supporting a possibly lossy coercion to an integer If that is the intent of __index__, the doc should say so more clearly. That clarification would change my answer to your question about range. (i.e. as the __int__ method allows for types like float and decimal.Decimal). This allows non-builtin objects to be used as sequence indices, elements of a slice definition, multiplies in sequence repetition, etc. Can be invoked explicitly from Python code via operator.index() Removing the circularity from the definitions of __index__ and operator.index doesn't have a great deal to do with the docstrings in numbers.py, though. It is both related and needed though. IE, it is hard to answer questions about what to to with .index if the intended meaning of .index is not very clear ;-). -- Terry Jan Reedy ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] [Python-checkins] r87445 - python/branches/py3k/Lib/numbers.py
On Fri, Dec 24, 2010 at 4:41 AM, eric.araujo python-check...@python.org wrote: Author: eric.araujo Date: Thu Dec 23 19:41:33 2010 New Revision: 87445 Log: Fix small inaccuracy: there is no index function Yes, there is, it just isn't a builtin - it lives in the operator module. def __index__(self): - index(self) + someobject[self] return int(self) Changing the docstring to say operator.index(self) would be the clearest solution here. (Choosing to accept arbitrary index objects as integer equivalents is up to the object being indexed, just like interpreting slices is - a dict, for example, will never invoke __index__ methods). Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
