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Date: Fri, 12 Dec 2014 18:38:42 +1100
Subject: Re: Extension of while syntax
From: Chris Angelico <rosuav@gmail.com>
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On Fri, Dec 12, 2014 at 6:10 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
> Chris Angelico <rosuav@gmail.com>:
>
>> You could deduplicate it by shifting the condition:
>>
>> while True:
>>     value = get_some_value()
>>     if value not in undesired_values: break
>>
>> But I'm not sure how common this idiom actually is.
>
> Extremely common, and not only in Python.

Something like it is certainly common, but to justify dedicated
syntax, the pure form has to be so amazingly common as to merit it. As
soon as you modify the pure form in any way, you need the statement
form, for full flexibility.

ChrisA