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From: jbdp@jenny.UUCP (Julian Pardoe)
Newsgroups: net.lang
Subject: Re(3): Varieties of conditional statement
Message-ID: <271@jenny.UUCP>
Date: Fri, 18-Oct-85 20:33:40 EDT
Article-I.D.: jenny.271
Posted: Fri Oct 18 20:33:40 1985
Date-Received: Wed, 23-Oct-85 04:56:16 EDT
Organization: U of Cambridge Comp Lab, UK
Lines: 39
Xpath: kcl-cs neon

> > Syntactically, there's no reason why we couldn't have something like:
> >     IF c THEN DECLARE a : INTEGER; ... ENDIF
>
> As, in fact, you do in Algol68.
>
>    IF c THEN INT a; ... FI

In fact you can do more than that:

   IF INT x; read (x); x < 0 THEN ...x... ELSE ...x... FI

and there is of course the all-purpose WHILE loop:

C Loop Type                    A68 Equivalent
===========                    ==============

while (e) do s;                WHILE e DO s OD

do s while (e);                WHILE s; e DO SKIP OD;

for (;;) {                     WHILE s1; e DO s2 OD;
   s1;
   if (e) break;
   s2;
}


Algol-68: love its syntax (except unlabelled CASEs),
          hate its semantics... (especially MODEs)

Julian Pardoe

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