Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!rutgers!dptg!ulysses!andante!alice!ark
From: ark@alice.UUCP (Andrew Koenig)
Newsgroups: comp.lang.c
Subject: Re: comma operator
Message-ID: <9741@alice.UUCP>
Date: 4 Aug 89 17:36:24 GMT
References: <10099@mpx2.mpx.com> <93@microsoft.UUCP> <10100@mpx2.mpx.com> <3287@ohstpy.mps.ohio-state.edu>
Organization: AT&T Bell Laboratories, Liberty Corner NJ
Lines: 23

In article <3287@ohstpy.mps.ohio-state.edu>, SMITHJ@ohstpy.mps.ohio-state.edu writes:

> Maybe I'm mistaken, but I'm sure that all the documentation I've read warns
> that the *comma* operator ----does not----- guarantee evaluation in any order.
> Specifically, the Microsoft 5.0 manual mentions this.

You're mistaken.

K&R, second edition, page 209:

	A pair of expressions separated by a comma is evaluated
	left-to-right, and the value of the left expression is
	discarded.  The type and value of the result are the type
	and value of the right operand.  All side effects from the
	evaluation of the left operand are completed before
	beginning evaluation of the right operand.

Perhaps you should check your Microsoft manual again; if it really
says that evaluation order of comma is undefined, I suggest a letter
to Microsoft [and hope their compiler doesn't get it wrong too!]
-- 
				--Andrew Koenig
				  ark@europa.att.com