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From: jlg@lanl.gov (Jim Giles)
Newsgroups: comp.lang.c
Subject: Re: ambiguous ?
Message-ID: <14102@lanl.gov>
Date: 20 Oct 89 23:02:09 GMT
References: <1989Oct20.175352.20598@utzoo.uucp>
Organization: Los Alamos National Laboratory
Lines: 22

From article <1989Oct20.175352.20598@utzoo.uucp>, by henry@utzoo.uucp (Henry Spencer):
> [...]Personally, my view is that code which relies on order of evaluation
> within expressions -- except in a few well-defined cases like C's && and
> || operators -- is broken even if the language specifies a precise meaning.

Gee, isn't it interesting that the only order dependent behaviour you
are willing to trust are the "well-defined" && and || operators.  Those
also happen to be the only ones (besides commas - which you presumably
also allow) that enforce order.  This is another one of those "Anything
C does is right, everything else is not" arguments.  Presumably, if C
made argument evaluation in function calls "well-defined", you would
would have no qualms depending on their order either.  Since that has
been the point I've tried to make all along - I rest my case.

> [...]                                                    The purpose of
> a programming language is to make the algorithm executable.  This always
> involves compromises.

If it involves compromises of correctness, the language is not worth
pursuing.  If it involves _unnecesasary_ compromises of efficiency,
the language is in need of modification.  C requires one or the other
compromise.