Path: utzoo!mnetor!uunet!mcvax!unido!sbsvax!greim
From: greim@sbsvax.UUCP (Michael Greim)
Newsgroups: comp.bugs.4bsd
Subject: Re: csh arithmetic bug
Message-ID: <478@sbsvax.UUCP>
Date: 12 Apr 88 14:13:41 GMT
Organization: Universitaet des Saarlandes, D-6600 Saarbruecken, FRG
Lines: 31
Keywords: csh arithmetic bugs

In <23570@ucbvax.BERKELEY.EDU> Paul Heckbert writes :
>Beware of doing arithmetic in csh, it's buggy!
>
>The command	@ x = 0 - 1 + 2		sets x to -3	(should be 1)
>
>The command	@ x = 0 - 1 - 2		sets x to 1	(should be -3)
>
>(same error with Sun UNIX 3.5 on Sun3 and 4.3 BSD on Vax780)
>
>csh must be parsing right-associatively by mistake!
>Division has a similar problem.
>
>It's hard to believe that a bug like this would persist for 8 years.

I just checked: the 4.3BSD manual does not mention any peculiarities.
But according to the SUN manual, * / % + and - are right associative.
(Maybe they just corrected the manual to conform with the program :-)

Does this weird behavior require fixing ? (should we vote ? :-)

	Michael

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