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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 6 May 2011 17:51:44 -0600
Subject: Re: checking if a list is empty
To: Python <python-list@python.org>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:4875

On Fri, May 6, 2011 at 4:21 PM, Philip Semanchuk <philip@semanchuk.com> wro=
te:
> What if it's not a list but a tuple or a numpy array? Often I just want t=
o iterate through an element's items and I don't care if it's a list, set, =
etc. For instance, given this function definition --
>
> def print_items(an_iterable):
> =A0 =A0if not an_iterable:
> =A0 =A0 =A0 =A0print "The iterable is empty"
> =A0 =A0else:
> =A0 =A0 =A0 =A0for item in an_iterable:
> =A0 =A0 =A0 =A0 =A0 =A0print item
>
> I get the output I want with all of these calls:
> print_items( list() )
> print_items( tuple() )
> print_items( set() )
> print_items( numpy.array([]) )

But sadly it fails on iterators:
print_items(xrange(0))
print_items(-x for x in [])
print_items({}.iteritems())