CSI Lisp

[Jonathan A Rees <JAR@MIT-MC.ARPA>]

    Date: Fri 12 Jul 85 21:45:05-PDT
    From: Andy Freeman <ANDY at SU-SUSHI>

    Right now, it looks like CSI Lisp's claim to being T is irresponsible.

Note that Jim didn't claim that CSI Lisp was T; in fact, he said it was
not:

    Date: Thu, 11 Jul 85 21:59:21 EDT
    From: Jim Meehan <Meehan at YALE.ARPA>

        [Freeman:] Price and wonderful support aside, is CSI Lisp T?

    [Meehan:] No.  ...

Only the ad in CACM claimed that it was.  Presumably an overzealous
marketing department, rather than a technical staff which knows better,
was responsible for the ad copy.  (Perhaps we can get the technical staff
to lobby marketing to change the ad for future runs?)

Note again, that Apollo CSI LISP is tail-recursive; only the versions
embedded in VAX LISP and LISP/VM aren't.  There are enough differences
besides this, however, that a truthful advertisement should say that CSI
LISP is derived from T (or something of that sort), rather than that it
is T.

    I don't have a copy of the CommonLisp manual, but I was under the
    impression that CommonLisp is tail-recursive.

Common Lisp is NOT defined to implement tail-recursions without net
stack growth.  It is not defined otherwise, however, so an
implementation is free to do whatever it wants.  I know of no
implementation which is properly tail-recursive, except the one from
LMI, where tail-recursion is a runtime switch (!), I think.

Jonathan