Re: Can anybody explain the '-' in a 2-D creation code?

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Date	Thu, 25 Jun 2015 18:18:15 -0700
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On 06/25/2015 06:07 PM, fl wrote:
> Hi,
>
> I read Ned's tutorial on Python. It is very interesting. On its last
> example, I cannot understand the '_' in:
>
>
>
> board=[[0]*8 for _ in range(8)]
>
>
> I know  '_' is the precious answer, but it is still unclear what it is
> in the above line. Can you explain it to me?
>
>
> Thanks,

He uses _ to indicate a variable whose name and value he does not care 
about, but it *is* a valid variable name.

He could have used
   ... for i in range ...
or
   ... for unused_variable in range ...

This is a valid, though probably unclear, use of that same name:

 >>> _ = 123
 >>> print(_)
123
 >>>

Gary Herron

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Thread

Can anybody explain the '-' in a 2-D creation code? fl <rxjwg98@gmail.com> - 2015-06-25 18:07 -0700
  Re: Can anybody explain the '-' in a 2-D creation code? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-26 02:23 +0100
    Re: Can anybody explain the '-' in a 2-D creation code? fl <rxjwg98@gmail.com> - 2015-06-25 18:40 -0700
      Re: Can anybody explain the '-' in a 2-D creation code? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-26 03:27 +0100
  Re: Can anybody explain the '-' in a 2-D creation code? André Roberge <andre.roberge@gmail.com> - 2015-06-25 18:24 -0700
  Re: Can anybody explain the '-' in a 2-D creation code? Atnakus Arzah <atnakus.arzah@gmail.com> - 2015-06-25 18:29 -0700
  Re: Can anybody explain the '-' in a 2-D creation code? Gary Herron <gary.herron@islandtraining.com> - 2015-06-25 18:18 -0700

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