Loop until condition is true

Charles Krug cdkrug at worldnet.att.net
Tue Jun 21 15:18:59 CEST 2005


On Tue, 21 Jun 2005 12:05:25 +0200, Magnus Lycka <lycka at carmen.se> wrote:
> Remi Villatel wrote:
>> while True:
>>     some(code)
>>     if final_condition is True:
>>         break
>>     #
>> #
>> 
>> What I don't find so "nice" is to have to build an infinite loop only to 
>> break it.
> 
> This is a common Python idiom. I think you will get used to it.
> 
> 
>> Is there a better recipe?
> 
> final_condition = False
> while not final_condition:
>      some(code)

To the OP, don't get hung up on the syntax we use to implement a loop.

I took my first programming class long enough ago that we had to do
things like this (roughly translating the FORTRAN IV I remember into
p-code)

To do:

while TrueCondition
    (loop body)

we'd have to write:

TopOfLoop:
if not TrueConditional goto loopEnd
   (loop body)
   goto TopOfLoop

loopEnd:

We were even required to write our source twice:

The first pass was "structured" and had to be proven correct.

The second pass was translated into something our compiler supported.

We still called it a "while loop" even though the syntax was icky.

When C came out with its built in looping, it was an unbelievable
luxury.




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