[Python-Dev] PEP 315 - do while

Fuzzyman fuzzyman at voidspace.org.uk
Tue Oct 3 12:00:18 CEST 2006

Nick Coghlan wrote:

>Hans Polak wrote:
>>Ok, I see your point. Really, I've read more about Python than worked with
>>it, so I'm out of my league here.
>>Can I combine your suggestion with mine and come up with the following:
>>      do:
>>          <setup code>
>>          <loop body>
>>          while <condition>
>>      else:
>>          <loop completion code>
>In my example, the 3 sections (<setup code>, <loop body> and <loop completion 
>code> are all optional. A basic do-while loop would look like this:
>       do:
>           <setup code>
>           while <condition>
>(That is, <setup code> is still repeated each time around the loop - it's 
>called that because it is run before the loop evaluated condition is evaluated)


This looks good.

The current idiom works fine, but looks unnatural :

while True:
    if <condition>:

Would a 'while' outside of a 'do' block (but without the colon) then be
a syntax error ?

'do:' would just be syntactic sugar for 'while True:' I guess.

Michael Foord


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