Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!water!watnot!watmath!clyde!rutgers!ames!cit-vax!usc-oberon!castor.usc.edu!blarson
From: blarson@castor.usc.edu.UUCP
Newsgroups: comp.lang.c
Subject: evaluation order, unary +, etc.
Message-ID: <1557@castor.usc.edu>
Date: Sat, 11-Apr-87 22:06:04 EST
Article-I.D.: castor.1557
Posted: Sat Apr 11 22:06:04 1987
Date-Received: Sun, 12-Apr-87 17:37:58 EST
Reply-To: blarson@castor.usc.edu.UUCP (Bob Larson)
Distribution: world
Organization: USC AIS, Los Angeles
Lines: 30

When I use parentheies in an expression, I do so for readability of
code and/or override operator presidence, NOT to force the calculation
to be done in that order.  Changing the meaning of parenthesies in C
would force me as a programer to write less readable code so the
optimizer could do it's job.

I do think having a way to force evalution order is not a bad idea, and
I'm not especially in love with the use of unary plus for it.  A cast
to volitile would be much better, it's saying what you mean.

	double a,b,c,d;
	
	a = (volitile double)(b + c) + d;

would mean calculate b+c before adding d.

If I was serious about proposing changes to C, I would probably
propose that the whole float/double portion be made optional.  I rarly
find them of any use, and can't justify having compiler/library
writers waste time on them.  (I am a full time programer, and can't
remember the last time I needed to to something in floating point.)
(OK, I admit this paragraph was added to show that not everyone uses C
for the same thing.  I think forcing parathasies to mean something
different than they currently do is just as bad for me as eliminating
floating point would be for you.)
-- 
Bob Larson
Arpa: Blarson@Usc-Eclb.Arpa
Uucp: (several backbone sites)!sdcrdcf!usc-oberon!castor.usc.edu!blarson
			seismo!cit-vax!usc-oberon!castor.usc.edu!blarson