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Re: De-tupleizing a list

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On Tuesday 26 April 2011 22:19:08 Gnarlodious wrote:
> On Apr 25, 10:59 pm, Steven D'Aprano wrote:
> > In Python 3, map becomes lazy and returns an iterator
> > instead of a list, so you have to wrap it in a call to
> > list().
> 
> Ah, thanks for that tip. Also works for outputting a tuple:
> list_of_tuples=[('0A',), ('1B',), ('2C',), ('3D',)]
> 
> #WRONG:
> (x for (x,) in list_of_tuples)
> <generator object <genexpr> at 0x1081ee0>
> 
> #RIGHT:
> tuple(x for (x,) in list_of_tuples)
> 
> Thanks everyone for the abundant help.
> 
> -- Gnarlie

I think you already have the following:
>>> t = [('0A',), ('1B',), ('2C',), ('3D',)]
>>> ls = [v[0] for v in t]
>>> ls
['0A', '1B', '2C', '3D']
>>> 

I would prefer that to using a ready made module,  as it would 
be quicker than learning about the module,  OTH, learning about 
a module may be useful for other problems.  A standard dilema...

The above quote of code is in Idle3, running Python 3.1.

OldAl.
-- 
Algis
http://akabaila.pcug.org.au/StructuralAnalysis.pdf

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Thread

De-tupleizing a list Gnarlodious <gnarlodious@gmail.com> - 2011-04-25 20:28 -0700
  Re: De-tupleizing a list CM <cmpython@gmail.com> - 2011-04-25 20:42 -0700
    Re: De-tupleizing a list Gnarlodious <gnarlodious@gmail.com> - 2011-04-25 20:52 -0700
  Re: De-tupleizing a list "Littlefield, Tyler" <tyler@tysdomain.com> - 2011-04-25 21:38 -0600
  Re: De-tupleizing a list Philip Semanchuk <philip@semanchuk.com> - 2011-04-25 23:38 -0400
  Re: De-tupleizing a list Paul Rubin <no.email@nospam.invalid> - 2011-04-25 21:08 -0700
    Re: De-tupleizing a list John Connor <john.theman.connor@gmail.com> - 2011-04-25 23:29 -0500
  Re: De-tupleizing a list Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-26 04:59 +0000
    Re: De-tupleizing a list rusi <rustompmody@gmail.com> - 2011-04-25 22:26 -0700
    Re: De-tupleizing a list Gnarlodious <gnarlodious@gmail.com> - 2011-04-26 05:19 -0700
      Re: De-tupleizing a list Algis Kabaila <akabaila@pcug.org.au> - 2011-04-27 04:30 +1000
        Re: De-tupleizing a list Hans Georg Schaathun <hg@schaathun.net> - 2011-04-26 21:11 +0100
          Re: De-tupleizing a list Ethan Furman <ethan@stoneleaf.us> - 2011-04-26 13:37 -0700
            Re: De-tupleizing a list Hans Georg Schaathun <hg@schaathun.net> - 2011-04-26 21:58 +0100
  Re: De-tupleizing a list Raymond Hettinger <python@rcn.com> - 2011-04-26 14:16 -0700
  Re: De-tupleizing a list John Pinner <funthyme@gmail.com> - 2011-04-27 03:56 -0700
    Re: De-tupleizing a list Algis Kabaila <akabaila@pcug.org.au> - 2011-04-28 05:31 +1000

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