Subject: Re: Why is 'if' a special form?
From: rpw3@rigden.engr.sgi.com (Rob Warnock)
Date: 1998/07/27
Newsgroups: comp.lang.scheme
Message-ID: <6pisrk$256s7@fido.engr.sgi.com>
Last Friday, I wrote:
+---------------
| ...in quite a few popular implementations [square brackets] are considered
| completely equivalent to parens...  Particularly in Scsh and MzScheme code,
| the square brackets get used a *lot* for the elements of "let" bindings...
+---------------

Several people[*] wrote to let me know that Scsh *doesn't* do this.
I apologize for the mistake. I don't where I got the idea that it did.
[I *thought* I saw it in the SU-HTTP source... WRONG!]

Anyway, there are certainly plenty of other inplementations which *do*
treat [] the same as (), including MzScheme, SCM (and thus probably Guile),
Gambit Scheme, Fool's Lisp, and probably others. But certainly not enough
to be able to depend on it if you are trying to write portable Scheme code
(assuming you don't think that's an oxymoron).


-Rob


[*] Thanks to smd@ebone.net & emarsden@mail.dotcom.fr for setting me straight.

-----
Rob Warnock, 7L-551		rpw3@sgi.com   http://reality.sgi.com/rpw3/
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