Re: (objects as) mutable dictionary keys

From: Steve Holden (steve_at_holdenweb.com)
Date: 01/14/05 

Date: Fri, 14 Jan 2005 17:22:20 -0500

Antoon Pardon wrote:

> Op 2005-01-14, Peter Maas schreef <peter@somewhere.com>:
>
>>I have summarized the discussion about the usability of lists (and
>>and other mutable types) as dictionary keys and put it into the
>>Python wiki.URL: http://www.python.org/moin/DictionaryKeys.
>>
>>This summary might be used as a reference should the 'mutable
>>dictionary keys' issue come up again in c.l.py.
>>
>
> I had a look and I think you should correct the followingr:
>
> Dictionary lookup with mutable types like lists is a source of
> unpleasant surprises for the programmer and therefore impossible in
> Python.
>
Better, perhaps, to say:

   Dictionary lookup with mutable types like lists can be a
   source of unpleasant surprises for the programmer and
   therefore not recommended in Python.

>
> It is not impossible in Python. It may be discouraged but it is not
> impossible since I have already done so.
>
If I discouraged you from shooting yourself in the foot would you do
that too?

some-people-just-won't-be-told-ly y'rs - steve 

-- 
Steve Holden               http://www.holdenweb.com/
Python Web Programming  http://pydish.holdenweb.com/
Holden Web LLC      +1 703 861 4237  +1 800 494 3119

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