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To: python-list@python.org
From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Simplest/Idiomatic way to count files in a directory (using pathlib)
Date: Tue, 23 Jun 2015 12:17:34 -0400
References: <mailman.712.1435012328.13271.python-list@python.org> <87k2uvjjjv.fsf@nightsong.com>
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On 6/22/2015 9:32 PM, Paul Rubin wrote:
> Travis Griggs <travisgriggs@gmail.com> writes:
>> The following seems to obtuse/clever for its own good:
>>      return sum(1 for _ in self.path.iterdir())

I disagree.  For one who understands counting and Python, this is a 
direct way to define the count of a finite iterable.  A functionalist 
would prefer it to the obvious 3-line version with a for statement.

> I've generally done something like that.  I suppose it could be added to
> itertools.

itertools callables all produce iterators.  The above only consumes an 
iterable.

-- 
Terry Jan Reedy