Re: [newbie] A question about lists and strings

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Date	Fri, 10 Aug 2012 20:40:01 +1000
Subject	Re: [newbie] A question about lists and strings
From	Chris Angelico <rosuav@gmail.com>
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On Fri, Aug 10, 2012 at 8:31 PM, Mok-Kong Shen
<mok-kong.shen@t-online.de> wrote:
> This means there is no way of modifying a string at the top level
> via a function, excepting through returning a new value and assigning
> that to the string name at the top level. Please again correct me, if
> I am wrong.

Yes, but you can (ab)use a one-element list as a pointer.

>>> foo=["Hello"]
>>> def mutate(ptr):
	ptr[0]="World"

>>> mutate(foo)
>>> print(foo[0])
World

But it's probably worth thinking about exactly why you're wanting to
change that string, and what you're really looking to accomplish.
There may well be a better way.

Chris Angelico

Thread

[newbie] A question about lists and strings Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-08-10 11:19 +0200
  Re: [newbie] A question about lists and strings Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 13:28 +0400
  Re: [newbie] A question about lists and strings Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 13:48 +0400
    Re: [newbie] A question about lists and strings Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-08-10 12:12 +0200
      Re: [newbie] A question about lists and strings Chris Angelico <rosuav@gmail.com> - 2012-08-10 20:37 +1000
      Re: [newbie] A question about lists and strings Dave Angel <d@davea.name> - 2012-08-10 06:37 -0400
      Re: [newbie] A question about lists and strings Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 14:56 +0400
        Re: [newbie] A question about lists and strings Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-08-10 13:08 +0200
      Re: [newbie] A question about lists and strings Dave Angel <d@davea.name> - 2012-08-10 06:56 -0400
      Re: [newbie] A question about lists and strings Chris Angelico <rosuav@gmail.com> - 2012-08-10 21:00 +1000
      Re: [newbie] A question about lists and strings Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 15:06 +0400
  Re: [newbie] A question about lists and strings Peter Otten <__peter__@web.de> - 2012-08-10 11:59 +0200
    Re: [newbie] A question about lists and strings Rotwang <sg552@hotmail.co.uk> - 2012-08-10 16:12 +0100
  Re: [newbie] A question about lists and strings Dave Angel <d@davea.name> - 2012-08-10 06:07 -0400
    Re: [newbie] A question about lists and strings Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-08-10 12:31 +0200
      Re: [newbie] A question about lists and strings Chris Angelico <rosuav@gmail.com> - 2012-08-10 20:40 +1000
        Re: [newbie] A question about lists and strings Mok-Kong Shen <mok-kong.shen@t-online.de> - 2012-08-10 12:48 +0200
          Re: [newbie] A question about lists and strings Dave Angel <d@davea.name> - 2012-08-10 06:58 -0400
      Re: [newbie] A question about lists and strings Dave Angel <d@davea.name> - 2012-08-10 06:53 -0400

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