Re: while expression feature proposal

From	Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de>
Newsgroups	comp.lang.python
Subject	Re: while expression feature proposal
Date	2012-10-25 22:49 +0200
Organization	A newly installed InterNetNews server
Message-ID	<k6c8kh$lqj$1@r03.glglgl.gl> (permalink)
References	(3 earlier) <mailman.2803.1351119286.27098.python-list@python.org> <7x7gqf1na2.fsf@ruckus.brouhaha.com> <mailman.2807.1351121989.27098.python-list@python.org> <k6apaa$eid$1@r03.glglgl.gl> <mailman.2854.1351183039.27098.python-list@python.org>

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Am 25.10.2012 18:36 schrieb Ian Kelly:
> On Thu, Oct 25, 2012 at 1:21 AM, Thomas Rachel
> <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de>
> wrote:
>>> j = next(j for j in iter(partial(randrange, n), None) if j not in
>>> selected)
>>
>>
>> This generator never ends. If it meets a non-matching value, it just skips
>> it and goes on.
>
> next() only returns one value.  After it is returned, the generator is
> discarded, whether it has ended or not.  If there were no valid values
> for randrange to select, then it would descend into an infinite loop.
> But then, so would the dropwhile and the original while loop.

You are completely right. My solution was right as well, but didn't 
match the problem...

Yours does indeed return one random value which is guaranteed not to be 
in selected.

Mine returns random values until the value is not in selected. I just 
misread the intention behind the while loop...

Thomas

Thread

Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-24 16:54 -0600
  Re: while expression feature proposal Paul Rubin <no.email@nospam.invalid> - 2012-10-24 16:08 -0700
    Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-24 17:39 -0600
      Re: while expression feature proposal Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-10-25 09:21 +0200
        Re: while expression feature proposal Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-10-25 12:12 +0200
        Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-25 10:36 -0600
          Re: while expression feature proposal Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-10-25 22:49 +0200
            Re: while expression feature proposal Dan Loewenherz <dloewenherz@gmail.com> - 2012-10-25 22:12 -0700
              Re: while expression feature proposal Paul Rubin <no.email@nospam.invalid> - 2012-10-25 23:06 -0700
                Re: while expression feature proposal Chris Angelico <rosuav@gmail.com> - 2012-10-26 17:23 +1100
                Re: while expression feature proposal Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-26 09:43 +0000
                Re: while expression feature proposal Dan Loewenherz <dloewenherz@gmail.com> - 2012-10-26 08:29 -0700
                Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-26 09:42 -0600
                Re: while expression feature proposal Paul Rubin <no.email@nospam.invalid> - 2012-10-26 09:10 -0700
                Re: while expression feature proposal Cameron Simpson <cs@zip.com.au> - 2012-10-27 09:03 +1100
                Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-26 16:48 -0600
                Re: while expression feature proposal Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-27 00:07 +0000
                Re: while expression feature proposal Paul Rubin <no.email@nospam.invalid> - 2012-10-26 20:43 -0700
                Re: while expression feature proposal Tim Chase <sed@thechases.com> - 2012-10-26 18:26 -0500
                Re: while expression feature proposal Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-26 19:41 -0400
                Re: while expression feature proposal Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-26 19:19 -0400
                Re: while expression feature proposal Chris Angelico <rosuav@gmail.com> - 2012-10-27 11:42 +1100
              Re: while expression feature proposal Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-26 19:12 -0400
                Re: while expression feature proposal Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-27 00:18 +0000
                Re: while expression feature proposal Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-26 20:27 -0400
                Re: while expression feature proposal Tim Chase <python.list@tim.thechases.com> - 2012-10-27 14:15 -0500
              Re: while expression feature proposal Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-10-26 19:51 -0400
        Re: while expression feature proposal Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-25 10:47 -0600
    Re: while expression feature proposal Paul Rudin <paul.nospam@rudin.co.uk> - 2012-10-25 10:35 +0100

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