Re: Unpaking Tuple

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Date	Sat, 6 Oct 2012 03:27:52 -0700
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Subject	Re: Unpaking Tuple
From	Chris Rebert <clp2@rebertia.com>
To	sajuptpm <sajuptpm@gmail.com>
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On Sat, Oct 6, 2012 at 3:09 AM, sajuptpm <sajuptpm@gmail.com> wrote:
> Hi,
>
> I am using python 2.6.
>
> I need a way to make following code working without any ValueError .
>>>> a, b, c, d = (1,2,3,4)
>>>> a, b, c, d = (1,2,3).
>
> Note: Number of values in the tuple will change dynamically.

Then you arguably want a list, not a tuple.

But at any rate:
shortfall = 4 - len(your_tuple)
your_tuple += (None,) * shortfall # assuming None is a suitable default
a, b, c, d = your_tuple

If you also need to handle the "too many items" case, use slicing:
a, b, c, d = your_tuple[:4]

Cheers,
Chris

Thread

Unpaking Tuple sajuptpm <sajuptpm@gmail.com> - 2012-10-06 03:09 -0700
  Re: Unpaking Tuple Chris Rebert <clp2@rebertia.com> - 2012-10-06 03:27 -0700
    Re: Unpaking Tuple Roy Smith <roy@panix.com> - 2012-10-06 08:46 -0400
      Re: Unpaking Tuple Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-06 15:08 +0000
        Re: Unpaking Tuple Thomas Bach <thbach@students.uni-mainz.de> - 2012-10-08 23:45 +0200
        RE: Unpaking Tuple "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-10-08 22:21 +0000
          Re: RE: Unpaking Tuple Bob Martin <bob.martin@excite.com> - 2012-10-09 07:07 +0100
            Re: Unpaking Tuple Dave Angel <d@davea.name> - 2012-10-09 02:29 -0400
              Re: Unpaking Tuple Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2012-10-09 10:22 +0300
                Re: mangled messages (was: Unpaking Tuple) Tim Chase <python.list@tim.thechases.com> - 2012-10-09 05:48 -0500
                Re: mangled messages (was: Unpaking Tuple) Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2012-10-09 15:05 +0300
                Re: mangled messages Tim Chase <python.list@tim.thechases.com> - 2012-10-09 09:26 -0500
            Re: Unpaking Tuple Grant Edwards <invalid@invalid.invalid> - 2012-10-09 14:11 +0000
            RE: RE: Unpaking Tuple "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-10-09 16:40 +0000
            Re: Unpaking Tuple Robert Miles <robertmiles@teranews.com> - 2012-11-18 19:14 -0600
            Re: Unpaking Tuple Hans Mulder <hansmu@xs4all.nl> - 2012-11-19 02:56 +0100
  Re: Unpaking Tuple woooee <woooee@gmail.com> - 2012-10-07 10:58 -0700
    Re: Unpaking Tuple Terry Reedy <tjreedy@udel.edu> - 2012-10-07 16:03 -0400

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