The rap against "while True:" loops

David C Ullrich ullrich at
Mon Oct 12 23:59:55 CEST 2009

kj wrote:
> I'm coaching a group of biologists on basic Python scripting.  One
> of my charges mentioned that he had come across the advice never
> to use loops beginning with "while True".  Of course, that's one
> way to start an infinite loop, 

Heh-heh: When I read this it occurred to me that another way to
start an infinite loop would be to make a post here on this topic.
Looking at the thread so far it appears I was right.

> but this seems hardly a sufficient
> reason to avoid the construct altogether, as long as one includes
> an exit that is always reached.  (Actually, come to think of it,
> there are many situations in which a bona fide infinite loops
> (typically within a try: block) is the required construct, e.g.
> when implementing an event loop.)
> I use "while True"-loops often, and intend to continue doing this
> "while True", but I'm curious to know: how widespread is the
> injunction against such loops?  Has it reached the status of "best
> practice"?
> TIA!
> kynn

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