[prev in list] [next in list] [prev in thread] [next in thread] 

List:       python-list
Subject:    Re: Use cases for del
From:       Ron Adam <rrr () ronadam ! com>
Date:       2005-07-10 17:59:46
Message-ID: mmdAe.150621$VH2.140093 () tornado ! tampabay ! rr ! com
[Download RAW message or body]

Reinhold Birkenfeld wrote:
> Ron Adam wrote:
> 
> 
>>>    >>> 'abc' is 'abcd'[:3]
>>>    False
>>
>>Well of course it will be false... your testing two different strings! 
>>And the resulting slice creates a third.
>>
>>Try:
>>
>>ABC = 'abc'
>>
>>value = ABC
>>if value is ABC:   # Test if it is the same object
>>    pass
> 
> 
> That's not going to buy you any time above the "is None", because identity-
> testing has nothing to do with the type of the object.

Ok, I retested it... Not sure why I was coming up with a small 
difference before.  <shrug>  It seemed strange to me at the time which 
is part of why I asked.

My point was using strings "could" work in same context as None,  (if 
None acted as del), with out a performance penalty.  Anyway, this is all 
moot as it's an solution to a hypothetical situation that is not a good 
idea.

> Additionally, using "is" with immutable objects is horrible.

Why is it "horrible"?  Oh nevermind.  ;-)


Cheers,
Ron


> Reinhold
-- 
http://mail.python.org/mailman/listinfo/python-list
[prev in list] [next in list] [prev in thread] [next in thread]