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Author loewis
Recipients Arfrever, docs@python, loewis, max, r.david.murray, terry.reedy
Date 2012-09-22.01:12:04
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Terry: can you propose an alternative wording? I don't think that the discussion of TypeError belongs into the description of NotImplemented, though.

IIUC, NotImplemented was added for performance reasons; returning a value is much faster than raising an exception. The return only requires an INCREF/DECREF pair, and a pointer identity test. The exception requires to create a new object, possibly a traceback, and a subclass check on exception matching.
Date User Action Args
2012-09-22 01:12:05loewissetrecipients: + loewis, terry.reedy, Arfrever, r.david.murray, docs@python, max
2012-09-22 01:12:05loewissetmessageid: <>
2012-09-22 01:12:04loewislinkissue15997 messages
2012-09-22 01:12:04loewiscreate