IF

[Greenberg at MIT-Multics]

Maclisp has effectively consigned progn to fairly obscure cases and
people who are trying to get away using AND without having to resor to COND.
The extra level of parentheses in COND makes me, at least, shun it
in cases where I know that I'm only going to have one consequent, and use
AND in these cases (I only use "my" IF macro in emacs extension code).
I don't think that saying "Ok, If is good for only 1 consequent or
anti-consequent, if you need more use COND" makes anything better
than it is now, or for that matter, makes a whole lot of sense. Similarly,
if IF needs progns to solve THAT issue, it is inutile too. I myself
am queasy about "keywords", but the more I think about the explanation
of Fexprs as "special forms" the more sense it makes.  Progn is a syntactic
kludge, like "end;" in PL/I.  Devising a "simplification" of the silly

lisp COND that forces people to use PROGN is no improvement. I have
faced several times thedifficulty of explaining Lisp: progn is a rough one;
given NOT using AND the way it was not intended, Maclisp makes
it so that it should almost never be neceessary.  I, for one, favor
keeping it that way.  And if the IF frob is not good enough for
"all" cases given that, let's not have it.