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From: bsmith@iuvax.UUCP (Bruce T. Smith)
Newsgroups: comp.lang.prolog
Subject: Re: PROLOG comment style
Message-ID: <2159@iuvax.UUCP>
Date: Sun, 7-Dec-86 01:04:14 EST
Article-I.D.: iuvax.2159
Posted: Sun Dec  7 01:04:14 1986
Date-Received: Sun, 7-Dec-86 20:58:14 EST
References: <157@its63b.ed.ac.uk>
Reply-To: bsmith@iuvax.UUCP (Bruce T. Smith)
Organization: Indiana University, Bloomington
Lines: 17

I like that kind of comment, too.  In the Prolog systems I've used, they are
only comments, so it's safe to extend it a bit.  For example:

	1) Give multiple specifications when appropriate.  E.g., foo(+X,-Y)
	   and foo(-X,+Y) might make sense for a clause, and are not the
	   same as foo(?X,?Y).

	2) For some patterns of instantiated variables a particular argument
	   may be ignored.  I use a prefix '_', like the anonymous variable.

	3) Use types, e.g., foo(+Int,-Float).

__________________________________________________________
Bruce T. Smith,			UUCP:	bsmith@iuvax
101 Lindley Hall		CSnet:	bsmith@indiana.edu
Indiana University		Phone:  (812) 335-2566
Bloomington, IN 47405