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Date: Tue, 26 Jul 2011 11:08:38 -0700
From: Ethan Furman <ethan@stoneleaf.us>
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To: Neil Cerutti <neilc@norwich.edu>
Subject: Re: Is this overuse a context manager?
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:10344

Neil Cerutti wrote:
> I use them all the time now, even when the resource being managed
> is used for just one line, and never need be assigned an explicit
> name. Is it good style, or annoying?
> 
>     with open(in_fname, newline='') as in_file:
>         folk = list(csv.DictReader(in_file))
> 
> The obvious alternative is:
> 
>     folk = list(csv.DictReader(open(in_fname, newline='')))

I can see that it might take some getting used to, but I suspect the 
context managers are the better style: it clearly denotes the lifespan 
of the managed object, and provides for resource clean-up.  (I know, 
files are already automatically cleaned up -- at least in cpython; but 
not every managed object will be a file.)

~Ethan~