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Date: Thu, 19 May 2011 04:41:21 +1000
Subject: Re: English Idiom in Unix: Directory Recursively
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:5725

On Thu, May 19, 2011 at 4:20 AM, Raymond Wiker <raw@rawmbp-2.local> wrote:
>> You are right that I assumed parent pointers of some description;
>> but it does demonstrate that tree walks can be done iteratively,
>> without keeping a stack of any sort.
>
> =A0 =A0 =A0 =A0Except that the chain of parent pointers *would* constitue=
 a
> stack.

Howso? It's part of your data structure, not part of your algorithm;
and it's not something that grows and shrinks as you traverse. These
considerations may be crucial if, for instance, you want to walk your
tree in a signal handler, and you don't know how much memory is
available to you...

Chris Angelico