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From: Kaz Kylheku <643-408-1753@kylheku.com>
Newsgroups: comp.lang.lisp
Subject: Re: Lisp history: IF, etc.
Date: Thu, 4 Apr 2024 03:53:00 -0000 (UTC)
Organization: A noiseless patient Spider
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On 2024-04-04, Alan Bawden <alan@csail.mit.edu> wrote:
> Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>
>    On Wed, 03 Apr 2024 14:15:14 -0400, Alan Bawden wrote:
>
>    > Other programming languages at the time (e.g. FORTRAN and ALGOL) only
>    > had conditional statements.
>
>    Algol60 had if-expressions, e.g.
>
>        a := if b then c else d
>
> 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.

Aha, that could also be the source of the idea that MacCarthy came up
with the ternary IF. (Is it documented whether he actually suggested the
three-operand one, or something more COND like that the committee
whittled down to the above form?)

-- 
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