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Re: Suggested feature: slice syntax within tuples (or even more generally)?

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Apparently Travis Oliphant of numpy would like this as well...

http://technicaldiscovery.blogspot.com/2011/06/python-proposal-enhancements-i-wish-i.html

On Wednesday, February 13, 2013 2:00:15 PM UTC-5, steph...@gmail.com wrote:
> Hello,
> 
> 
> 
> Would it be feasible to modify the Python grammar to allow ':' to generate slice objects everywhere rather than just indexers and top-level tuples of indexers?
> 
> 
> 
> Right now in Py2.7, Py3.3:
> 
>     "obj[:,2]" yields "obj[slice(None),2]"
> 
> but
> 
>     "obj[(:,1),2]" is an error, instead of "obj[(slice(None), 1), 2]"
> 
> 
> 
> Also, more generally, you could imagine this working in (almost?) any expression without ambiguity:
> 
>     "a = (1:2)" could yield "a = slice(1,2)"
> 
> 
> 
> See motivating discussion for this at:
> 
>     https://github.com/pydata/pandas/issues/2866
> 
> 
> 
> There might not be very many use cases for this currently outside of pandas, but apparently the grammar was already modified to allow '...' outside indexers and there's probably even fewer valid use cases for that:
> 
>     "e = ..." yields "e = Ellipsis"
> 
> 
> 
> Would there be any downside to changing the handling of ':' as well? It might even make the grammar simpler, in some ways, since indexers won't have to be treated specially.
> 
> 
> 
> Let me know if you have any thoughts.
> 
> 
> 
> Thanks!
> 
> Stephen

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Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-13 11:00 -0800
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Terry Reedy <tjreedy@udel.edu> - 2013-02-14 00:23 -0500
    Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-13 21:54 -0800
    Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-13 21:54 -0800
      Re: Suggested feature: slice syntax within tuples (or even more generally)? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-14 07:32 +0000
        Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 00:36 -0800
      Re: Suggested feature: slice syntax within tuples (or even more generally)? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-14 08:03 +0000
        Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 01:08 -0800
          Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 01:26 -0800
        Re: Suggested feature: slice syntax within tuples (or even more generally)? Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-14 11:58 -0700
          Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 14:01 -0800
          Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 14:01 -0800
            Re: Suggested feature: slice syntax within tuples (or even more generally)? Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-14 17:46 -0800
            Re: Suggested feature: slice syntax within tuples (or even more generally)? Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-14 17:46 -0800
  Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-13 22:06 -0800
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Duncan Booth <duncan.booth@invalid.invalid> - 2013-02-14 12:25 +0000
    Re: Suggested feature: slice syntax within tuples (or even more generally)? stephenwlin@gmail.com - 2013-02-14 07:56 -0800
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Andrew Robinson <andrew3@r3dsolutions.com> - 2013-02-25 01:10 +0000
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-25 03:28 -0700
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Terry Reedy <tjreedy@udel.edu> - 2013-02-25 06:23 -0500
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-25 09:54 -0700
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Andrew Robinson <andrew3@r3dsolutions.com> - 2013-02-25 09:47 +0000
  Re: Suggested feature: slice syntax within tuples (or even more generally)? Nobody <nobody@nowhere.com> - 2013-02-26 07:38 +0000

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