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From: david.reitter@gmail.com
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Subject: Re: to big nest level of recursion
Date: 4 Apr 2006 06:36:37 -0700
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David Kastrup:

> They cannot be formulated with iteration _without_ a stack.  But of
> course, when using a stack as a data structure, you can map any
> recursion onto iteration.

Yes, and such a stack is likely to be more space-efficient than a call
stack, as it can be manually optimized to only contain what's
necessary.

The interesting question here is, of course, whether elisp should
support recursion better than it does now, with larger call stacks and
the necessary optimization. It has survived decades without it...