Fixed mx.DateTime or alternative?

[Chris Barker]

"M.-A. Lemburg" wrote:

> >  >>> from mx import DateTime
> >  >>> dt = DateTime.now()
> >  >>> if dt==None: print 1

> 
> Side note:
> 
>         if x is None: ...
> 
> is a possible workaround which is faster than using "==" !

I don't think this is an DateTime bug. I had the name problem with
Numeric arrays, when rich comparison's were introduced:

>>> from Numeric import *
>>> a = array((1,2,3))
>>> a == None
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: function not supported for these types, and can't coerce to
supported types
>>>

This worked just fine with older versions of Python. 

a is None

works just fine, and I think is a cleaner way to code it anyway. 

In general, the introduction of rich comparisons means that if __eq__ is
defined, special code would have to be written that handles the " ==
None" case. "is None" just makes more sense.

-Chris



-- 
Christopher Barker,
Ph.D.                                                           
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