From: David Masover <ninja@...>
Date: 2009-10-02T02:57:55+09:00
Subject: Re: SystemStackError: stack level too deep > how make it deeper?

On Thursday 01 October 2009 05:05:13 am Simon Krahnke wrote:
> * Tony Arcieri <tony@medioh.com> (05:25) schrieb:
> > [Note:  parts of this message were removed to make it a legal post.]
> >
> > On Wed, Sep 30, 2009 at 1:55 PM, Jason Roelofs 
<jameskilton@gmail.com>wrote:
> >> Rewrite it to not be recursive.
> >
> > That advice is about as useful as "Rewrite it in a language other than
> > Ruby"

Somehow, I think rewriting a tail-recursive algorithm to not be tail-recursive 
is much, much faster than translating the algorithm to another language, 
especially if it's part of a larger program.

It is a bit like, when you go from C to Ruby, you learn to use each loops 
instead of for loops. An argument could be made that tail-recursion isn't 
idiomatic Ruby.

> But it's the only answer there is. Unrecognized tail recursion will kill
> every stack.

Technically, it's not -- Ruby _can_ do tail recursion. It's just not trivial 
to turn on, not portable, and I believe disables some debugging features.