Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!hpcc01!hpcuhb!hpcllla!hpcllca!walter
From: walter@hpcllca.HP.COM (Walter Murray)
Newsgroups: comp.std.c
Subject: Re: dollar signs in identifiers (was: warning: '/*' within comment)
Message-ID: <16490021@hpcllca.HP.COM>
Date: 8 Jun 90 22:29:35 GMT
References: <16812@haddock.ima.isc.com>
Organization: Hewlett Packard Calif. Language Lab
Lines: 37

Karl Heuer writes:

> (The Standard requires that the strictly conforming program
> 	#include <stdio.h>
> 	#define foo$bar /* define foo to be dollar-bar */
> 	#ifdef foo
> 	int main(void) { printf("yes\n"); return 0; }
> 	#else
> 	int main(void) { printf("no\n"); return 0; }
> 	#endif
> must print "yes"; normal VMS behavior would be to treat `foo$bar' as a single
> token and print "no".)

I don't see how this can be a strictly conforming program.  The source
character set is implementation-defined (page 11, lines 3-4), and there
is nothing in the standard that requires $ to be a member.  (See also
page 11, lines 29-32.)

In fact, I would have trouble convincing myself that either of the 
following is a strictly conforming program:

   /* Program 1 */ int main () { /* $ */ }
   /* Program 2 */ int main () { '$'; }

Any thoughts?

Looking at this from a different perspective, must a conforming
implementation on an 8-bit-byte machine be prepared to accept all
256 possible bytes in a string literal?  Must it map them to 256
distinct values?  I think not.  The mapping of source file characters
to the source character set in translation phase 1 is not defined
by the standard.

Walter Murray
-------------