[Python-bugs-list] [ python-Bugs-720908 ] datetime types don't work as bases

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Bugs item #720908, was opened at 2003-04-14 00:58
Message generated for change (Comment added) made by tim_one
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Category: Extension Modules
Group: Python 2.3
>Status: Closed
>Resolution: Fixed
Priority: 5
Submitted By: Tim Peters (tim_one)
Assigned to: Tim Peters (tim_one)
Summary: datetime types don't work as bases

Initial Comment:
This is probably shallow.  Assigned to Guido in case 
it's very shallow <wink>:

>>> from datetime import *
>>> class C(date):
...     def whatever(self):
...         return "oops"
>>> c = C(2002, 1, 1)
>>> c.whatever()
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
AttributeError: 'datetime.date' object has no 
attribute 'whatever'
>>> type(c)
<type 'datetime.date'>
>>>

Was reported on c.l.py.

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>Comment By: Tim Peters (tim_one)
Date: 2003-05-17 13:40

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I checked in changes (for 2.3b2) so that time, datetime, 
and timedelta are properly subclassable from Python too.  
That's all of 'em, so closing this now.

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Comment By: Guido van Rossum (gvanrossum)
Date: 2003-04-14 18:20

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Done; the rest is up to you!

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Comment By: Tim Peters (tim_one)
Date: 2003-04-14 18:02

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I think the date enhancement is fine -- check it in!  I'd leave off 
removing the basetype flag on the other types, though -- I 
expect we'll need to make them subclassable too.

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Comment By: Guido van Rossum (gvanrossum)
Date: 2003-04-14 13:26

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Here's a strawman fix. It makes 'date' a properly
subclassable type, and makes all the other types (except
tzinfo) non-subclassable.

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Comment By: Guido van Rossum (gvanrossum)
Date: 2003-04-14 08:04

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Well, one shallow thing becomes obvious when you write
c.__class__: it's date, not C! Back to Tim...

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