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2.3 list reverse() bug?

Robin Becker robin at jessikat.fsnet.co.uk
Thu Dec 25 06:18:39 EST 2003 
In article <d3c9c04.0312250303.561b119d at posting.google.com>, Mark Carter
<cartermark46 at ukmail.com> writes
>I did this:
>
>Python 2.3 (#46, Jul 29 2003, 18:54:32) [MSC v.1200 32 bit (Intel)] on
>win32
>
>>>> d1 = [1,2]
>>>> d2 = d1
>>>> d2.reverse()
>>>> print d1 #note: d1, not d2
>[2, 1]
>>>> 
>
>Surely that can't be right: d1 should still be [1,2]. If it is
>"right", then I expect that many people are in for a suprise.
Really need to get a life, but anyhow here goes. 

It's right. d1 & d2 both point to the same mutable object and sort is
done in place.

compare with this

>>> d1=[1,2]
>>> d2=d1
>>> d2[0]='a'
>>> d1['a', 2]
>>> 
-- 
Robin Becker
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