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Date: Thu, 12 Sep 2013 00:46:02 +1000
Subject: Re: Language design
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:53969

On Thu, Sep 12, 2013 at 12:32 AM, Neil Cerutti <neilc@norwich.edu> wrote:
> On 2013-09-11, Burak Arslan <burak.arslan@arskom.com.tr> wrote:
>> My favourite gotcha is this:
>>
>>     elt, = elts
>>
>> It's a nice and compact way to do both:
>>
>>     assert len(elts) == 0
>>     elt = elts[0]
>
> I'm confused. Your rewrite looks like an assertion error or an
> IndexError.

Presumably he meant to assert that the length is 1. If elts is a list,
then yes, these are equivalent, though the expanded form is actually a
bit different (since any iterable can be used).

ChrisA