Subject: Re: How to prevent cdr from capitalizing symbols?
From: (Rob Warnock)
Date: Tue, 28 Sep 2004 00:03:03 -0500
Newsgroups: comp.lang.lisp
Message-ID: <>
Kenny Tilton  <> wrote:
| Andrei wrote:
| > I wonder what's the background of the idea to read all the symbols in
| > "cap" case? Wouldn't it be more natural to leave them as they are?
| Good question. Ping the historians. I have only been on board for ten 
| years, still a newby myself.
| Maybe "Back In the Day" they were not worried about talking to other 
| languages, including case-sensitive languages...

Actually, I suspect it was the Teletype Model ASR33 (sometimes called the
Model 33 ASR), manufactured by the Teletype Corporation of Skokie, Ill.,
that was the basis for the problem. (Google for "teletype skokie asr33"
for lots & lots of history.)  ;-}  ;-}

Even though they used "8-level" ASCII (7-bits plus parity), they were
upper-case only. They responded to lower-case alphabetics by printing
the corresponding upper-case character, but the keyboard generated upper
case only. These machines were the workhorse terminals of their day,
and many operating systems were written on the assumption that their
consoles and remote terminals were ASR33s (or compatible). Even when
"glass TTYs" ["TTY" is a contraction of "teletypewriter] or "video
terminals" started to become available, the very first ones were also
upper-case only.

The later (and more expensive!) ASR37, on the other hand, was an upper-
and lower-case terminal (though still almost entirely mechanical, like
the ASR33). Quite prized for document text entry, it created a problem
for operating systems that assumed commands were uppercase-only. So the
solution was to map lowercase input characters to uppercase internally
when needed.

[Operating systems written much later, such as Unix, had to deal with
the opposite problem: Having mixed-case as the default, and having the
standard commands expecting lowercase, how to deal with those users who
still had only uppercase-only terminal? See "stty(1)" for the "iuclc"
and "xcase" terminal options.]

So I suspect that Lisp (or LISP, as it was spelled back then) grew up
in a time when uppercase-only terminals were still more common than
lowercase-capable ones.


Rob Warnock			<>
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