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Date: Mon, 7 Oct 2013 20:34:26 -0700
Subject: Re: Tail recursion to while iteration in 2 easy steps
From: Mark Janssen <dreamingforward@gmail.com>
To: Piet van Oostrum <piet@vanoostrum.org>
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Xref: csiph.com comp.lang.python:56345

>> Yeah, and this is where two models of computation have been conflated,
>> creating magical effects, confusing everybody.  I challenge you to get
>> down to the machine code in scheme and formally describe how it's
>> doing both.
>
> Which two models of computation are you talking about? And what magica; effects?

Well, I delineate all computation involving predicates (like lambda
calculus) between those using digital logic (like C).  These realms of
computation are so different, they are akin to mixing the complex
numbers with the real.  Yet hardly anyone points it out (I've
concluded that hardly anyone has ever noticed -- the Church-Turing
thesis has lulled the whole field into a shortcut in thinking which
actually doesn't pan out in practice).

> AFAIK there is no magic in computer science, although every sufficiently advanced ...

Ha!  That's very good.  I'm glad you catch the spirit of my rant.
"Any sufficiently advanced compiler can be substituted with magic to
the neophyte without a change in output."  A mini Liskov substitution.

-- 
MarkJ
Tacoma, Washington