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From: Gregory Ewing <greg.ewing@canterbury.ac.nz>
Newsgroups: comp.lang.python
Subject: Re: Python Iterables struggling using map() built-in
Date: Mon, 08 Dec 2014 18:06:44 +1300
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Terry Reedy wrote:
> However, this 'beautiful' code has a trap.  If one gets rid of the 
> seemingly unneeded temporary list res by telescoping the last two lines 
> into a bit too much into
> 
>             yield tuple(next(i) for i in iters)
> 
> we now have an infinite generator, because tuple() swallows the 
> StopIteration raised as a side-effect of next calls.

An excellent example of the kind of thing that PEP 479
is designed to catch! There couldn't be a better
advertisement for it. :-)

-- 
Greg