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From: Vito De Tullio <vito.detullio@gmail.com>
Subject: Re: Short-circuit Logic
Date: Mon, 27 May 2013 06:59:13 +0200
References: <51a2ab67$0$30002$c3e8da3$5496439d@news.astraweb.com> <20130527015754.GA81324@cskk.homeip.net>
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Xref: csiph.com comp.lang.python:46162

Cameron Simpson wrote:

>   if s is not None and len(s) > 0:
>     ... do something with the non-empty string `s` ...
> 
> In this example, None is a sentinel value for "no valid string" and
> calling "len(s)" would raise an exception because None doesn't have
> a length.

obviously in this case an `if s: ...` is more than sufficient :P

-- 
ZeD