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◅ Derivation of PL/I

Algol 68 design mistakes? ▻

Derivation of PL/I

In article <38aafe7a$0$26824@news.sanjose1.level3.net>,
Randall Hyde <rhyde@shoe-size.com> wrote:
>Tim Goodwin <tjg@star.le.ac.uk> wrote in message
>news:888opg$uem$1@ltpcg.star.le.ac.uk...
>> I think if you replace "binary" with "arithmetic", you'll find that the
>> rule is consistent.  It doesn't extend to logical operators.
>
>Why is   A &= B; allowed but A &&= B; is not allowed?

Like I said, assignment expresssions are consistent for arithmetic
operators, but don't extend to logical operators.  `&&' is a logical
operator (that is, it deals with things that are of Boolean type).

>Repeat complaint for >> and <<.

`>>' is an arithmetic operator, so the corresponding assignment
operator exists.

`>' is a logical operator, so there is no corresponding assignment
operator.

Tim.
--
Tim Goodwin   | "If you don't know what closures are, you probably don't
Leicester, UK | want to know what closures are." -- Larry Wall

Original headers:

From: tjg@star.le.ac.uk (Tim Goodwin)
Newsgroups: comp.lang.c,comp.programming,comp.lang.misc,
  comp.arch.embedded,comp.realtime,comp.lang.pl1
Subject: Re: Derivation of PL/I (was Usenet group for PL/M language)
Date: 17 Feb 2000 15:48:05 -0000
Message-ID: <88h58b$q79$1@ltpcg.star.le.ac.uk>
References: <%NNf4.14333$oJ5.28732@newsfeeds.bigpond.com>
  <881ftf$re5$1@relay1.dsccc.com> <888opg$uem$1@ltpcg.star.le.ac.uk>
  <38aafe7a$0$26824@news.sanjose1.level3.net>

△ comp.lang.misc △

◅ Derivation of PL/I

Algol 68 design mistakes? ▻