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Re: List Problem

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Date Sun, 23 Sep 2012 18:56:47 -0600
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On 9/23/2012 3:44 PM, jimbo1qaz wrote:
> On Sunday, September 23, 2012 2:31:48 PM UTC-7, jimbo1qaz wrote:
>> I have a nested list. Whenever I make a copy of the list, changes in one affect the other, even when I use list(orig) or even copy the sublists one by one. I have to manually copy each cell over for it to work.
>>
>> Link to broken code: http://jimbopy.pastebay.net/1090401
> No, actually that's the OK code. http://jimbopy.pastebay.net/1090494 is the broken one.

I've not been following this thread fully, but why not just use 
x=list(y) to copy the list?
The issue is that when you assign i=[1,2,3] and then j = i, j is just a 
reference to i, which is why you change either and the other changes.

-- 
Take care,
Ty
http://tds-solutions.net
The aspen project: a barebones light-weight mud engine:
http://code.google.com/p/aspenmud
He that will not reason is a bigot; he that cannot reason is a fool; he that dares not reason is a slave.

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Thread

List Problem jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-23 14:31 -0700
  Re: List Problem jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-23 14:44 -0700
    Re: List Problem Chris Angelico <rosuav@gmail.com> - 2012-09-24 07:57 +1000
    Re: List Problem Dave Angel <d@davea.name> - 2012-09-23 18:03 -0400
    Re: List Problem Chris Angelico <rosuav@gmail.com> - 2012-09-24 08:27 +1000
      Re: List Problem Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-23 22:37 +0000
        Re: List Problem Chris Angelico <rosuav@gmail.com> - 2012-09-24 08:45 +1000
    Re: List Problem Chris Angelico <rosuav@gmail.com> - 2012-09-24 08:30 +1000
    Re: List Problem "Littlefield, Tyler" <tyler@tysdomain.com> - 2012-09-23 18:56 -0600
    Re: List Problem Chris Angelico <rosuav@gmail.com> - 2012-09-24 11:52 +1000
  Re: List Problem Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-23 22:07 +0000
  Re: List Problem jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-23 15:44 -0700

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