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Re: How to print something only if it exists?

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From Emile van Sebille <emile@fenx.com>
Subject Re: How to print something only if it exists?
Date Thu, 06 Sep 2012 11:19:09 -0700
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On 9/6/2012 10:59 AM tinnews@isbd.co.uk said...
> I want to print a series of list elements some of which may not exist,
> e.g. I have a line:-
>
>       print day, fld[1], balance, fld[2]
>
> fld[2] doesn't always exist (fld is the result of a split) so the
> print fails when it isn't set.
>
> I know I could simply use an if but ultimately there may be more
> elements of fld in the print and the print may well become more
> complex (most like will be formatted for example).  Thus it would be
> good if there was some way to say "print this if it exists".
>
You may be better off ensuring that fld is an appropriate length.  One
way may be tweaking the split to return the right numbers of elements:

 >>> T = "1,2,3"
 >>> flds = (T+","*5).split(",")[:5]
 >>> flds
['1', '2', '3', '', '']

Emile

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Thread

How to print something only if it exists? tinnews@isbd.co.uk - 2012-09-06 18:59 +0100
  Re: How to print something only if it exists? Emile van Sebille <emile@fenx.com> - 2012-09-06 11:19 -0700
  Re: How to print something only if it exists? Dave Angel <d@davea.name> - 2012-09-06 14:18 -0400
    Re: How to print something only if it exists? tinnews@isbd.co.uk - 2012-09-08 11:02 +0100
      Re: How to print something only if it exists? Dave Angel <d@davea.name> - 2012-09-08 07:08 -0400
  Re: How to print something only if it exists? Terry Reedy <tjreedy@udel.edu> - 2012-09-06 15:34 -0400
  Re: How to print something only if it exists? Hans Mulder <hansmu@xs4all.nl> - 2012-09-07 11:37 +0200
  Re: How to print something only if it exists? Roy Smith <roy@panix.com> - 2012-09-07 09:16 -0400
  RE: How to print something only if it exists? "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-09-13 17:48 +0000

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