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From: Alan Bawden <alan@csail.mit.edu>
Newsgroups: comp.lang.lisp
Subject: Re: Lisp history: IF, etc.
Date: Fri, 12 Apr 2024 14:53:46 -0400
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albert@spenarnc.xs4all.nl writes:

   In article <86cyr6pb2l.fsf@williamsburg.bawden.org>,
   Alan Bawden  <alan@csail.mit.edu> wrote:
   >Lisp doesn't really have statements _because_ McCarthy invented the
   >conditional expression.  That's kind of the point.  Other programming
   >languages at the time (e.g. FORTRAN and ALGOL) only had conditional
   >statements.  McCarthy invented the conditional expression and thus
   >created the first expression-only programming language.

   It is a common mistake to refer to ALGOL simple.
   Algol60 and algol68 are different beast altogether.

   algol68 has conditional expressions:
       a := 'if' summer 'then' 40 'else' -10 'fi' ;
   and even a short hand:
       a:= (summer|40|-10);

Actually Algol 60 _does_ have conditional expressions, it's Algol 58
that doesn't have them.  As I wrote myself last week elsewhere in this
thread:

    Ah yes, the history is slightly more complicated than I remembered.
    Algol 58 did not have conditional expressions.  But McCarthy then
    joined the Algol committee and he suggested that they add
    conditional expressions.  And so they do appear in Algol 60.

And when I wrote "ALGOL" in the message you quoted, I had forgtten about
Algol 58 entirely...

- Alan