Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!ken
From: ken@cs.rochester.edu (Ken Yap)
Newsgroups: comp.lang.pascal
Subject: Re: Funny evaluation of functions
Message-ID: <1989Aug29.231308.13734@cs.rochester.edu>
Date: 29 Aug 89 23:13:08 GMT
References: <20715@adm.BRL.MIL> <616@lehi3b15.csee.Lehigh.EDU> <4357@cps3xx.UUCP> <3007@mace.cc.purdue.edu>
Reply-To: ken@cs.rochester.edu.UUCP (Ken Yap)
Organization: U of Rochester, CS Dept, Rochester, NY
Lines: 13

|And I should have made it clearer when I posted my answer several days ago
|that I was referring to the standard, which I had in front of me at the time.
|
|I just assumed that when I said that "if the function 'one' has side
|effects, then the result of x*one(x) is implementation-dependent", people
|would know that I meant THE STANDARD SAYS that the result is
|implementation-dependent.  What other basis could I possibly have had for
|making the statement?  Certainly not by trying the program on different
|compilers, which proves nothing.  The implementation could be wrong.

Yes indeed. The standard is even more explicit than that.  The order of
evaluation of the operands of a binary operator is undefined and total
evaluation is not required in some cases. See J&W, 3rd Ed.