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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