dirwalk.py generator version of os.path.walk
Just van Rossum
just at xs4all.nl
Thu Feb 28 05:36:59 EST 2002
In article <a5kv49$ae8$2 at news.idiom.com>,
jimd at vega.starshine.org (Jim Dennis) wrote:
> > I wrote a different implementation of this general concept at:
>
> > http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/105873
>
> > You don't really need to keep a stack of directories and push/pop
> > things, because with generators you can recurse instead.
>
> >Tom
>
> But recursion is likely to cost more. The only state I need
> to keep is my current "todo" list of directories. A recursion
> would store functional state (unless Python supported tail-end
> recursion). So the append/pop (total cost, 3 lines of code)
> seems like the lightest weight way to do this.
Why don't you try it out? Setting up a generator is as expensive as
calling a function, but resuming or yielding a generator is _very_ cheap.
I personally find the recursive version clearer.
Just
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