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From: joel@decwrl.UUCP (Joel McCormack)
Newsgroups: net.lang.c,net.lang.mod2
Subject: Pointer dereferencing^^^^^^ in Modula-2
Message-ID: <679@decwrl.UUCP>
Date: Thu, 21-Feb-85 16:42:58 EST
Article-I.D.: decwrl.679
Posted: Thu Feb 21 16:42:58 1985
Date-Received: Fri, 22-Feb-85 11:42:47 EST
Organization: DEC Western Software Lab, Los Altos, CA
Lines: 17
Xref: utcs net.lang.c:4340 net.lang.mod2:175

From Mark Wittenberg:

- My enthusiasm was tempered when I noticed that it does NOT allow "ptr^^";
- you must use a run-time temp variable.  Anybody know why the change?

The EBNF production is

designator = qualident {"." ident | "[" ExpList "]" | "^"}.

Since {} means 0 or more times, qualident^^^^^^^^^^^^^^ is perfectly legal.
I've never actually had occasion to use this construct.  I don't know of any
reason why a specific implementation of Modula-2 would restrict this.


-- 
- Joel McCormack {ihnp4 decvax ucbvax allegra}!decwrl!joel
		 joel@decwrl.arpa