Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!cmcl2!lanl!jlg
From: jlg@lanl.gov (Jim Giles)
Newsgroups: comp.lang.fortran
Subject: Re: *THE SPECIAL CASE* (was: function side effects)
Message-ID: <3959@lanl.gov>
Date: 21 Sep 88 19:14:34 GMT
References: <3994@h.cc.purdue.edu>
Organization: Los Alamos National Laboratory
Lines: 22

From article <3994@h.cc.purdue.edu>, by ags@h.cc.purdue.edu (Dave Seaman):
> Now, I will ask my question one last time:  why is my code example 
> illegal?
> 

The example you gave appears to be legal.  The optimization I gave for
your example also appears to be legal.  It appears that the semantics
of Fortran may be ambiguous in this case.  I claim that any case in which
the semantics of a programming language are ambiguous is a case which
the programmer should regard as illegal.  I regard multiple side effects
in C expressions as illegal - because the semantics of such things are
ambiguous

YES!!! I ADMIT IT!!!! You have found a case that I thought was illegal
and now it appears to be _merely_ ambiguous in meaning.  Now, are you still
going to maintain that it should be used by programmers (as you have been
doing).  Or, do you think it should have the same status as the 'i=f(i++)'
type of operation in C?  That is, it should be illegal but the committee
hasn't said so yet.

J. Giles
Los Alamos