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Re: Iterate over text file, discarding some lines via context manager

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Date Sat, 29 Nov 2014 05:02:34 +1100
Subject Re: Iterate over text file, discarding some lines via context manager
From Chris Angelico <rosuav@gmail.com>
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On Sat, Nov 29, 2014 at 4:55 AM, Marko Rauhamaa <marko@pacujo.net> wrote:
> I think the OP can learn from the comparison. One question, many
> lessons:
>
>  * Here's how you write a generator.
>
>  * Here's how you write a context manager class. You run into those
>    quite often as well.
>
>  * See how much more suitable a generator is in this case.
>
> No need to shoot down those who only try to be helpful.

Since we're so good at it on this list, I will nit-pick: that's not a
context manager class, that's an iterator class. A context manager has
__enter__ and __exit__, an iterator has __iter__ (returning self) and
__next__ (returning or raising StopIteration).

ChrisA

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Iterate over text file, discarding some lines via context manager "fetchinson ." <fetchinson@googlemail.com> - 2014-11-28 16:04 +0100
  Re: Iterate over text file, discarding some lines via context manager "ast" <nomail@invalid.com> - 2014-11-28 18:06 +0100
    Re: Iterate over text file, discarding some lines via context manager Dave Angel <davea@davea.name> - 2014-11-28 12:40 -0500
      Re: Iterate over text file, discarding some lines via context manager Marko Rauhamaa <marko@pacujo.net> - 2014-11-28 19:55 +0200
        Re: Iterate over text file, discarding some lines via context manager Chris Angelico <rosuav@gmail.com> - 2014-11-29 05:02 +1100
          Re: Iterate over text file, discarding some lines via context manager Marko Rauhamaa <marko@pacujo.net> - 2014-11-28 20:04 +0200

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