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From: drw@cullvax.UUCP (Dale Worley)
Newsgroups: comp.emacs
Subject: &optional keywords in function parameters
Message-ID: <1296@cullvax.UUCP>
Date: Fri, 19-Jun-87 10:50:16 EDT
Article-I.D.: cullvax.1296
Posted: Fri Jun 19 10:50:16 1987
Date-Received: Mon, 22-Jun-87 02:04:29 EDT
Organization: Cullinet Software, Westwood, MA, USA
Lines: 15

steve@et.UUCP (Steve Hole) writes:
>    Does anyone have a good definition of exactly what the &optional
> keyword does in the function parameter definitions.   I have the
> general idea and I wish to use it for some of my functions, but I
> don't know some things like:

If the parameter isn't given, it value is nil.  Presumably, all
perameters can be optional.  There may be a limit on the number of
parameters, but I'll bet it's large.

Dale
-- 
Dale Worley	Cullinet Software		ARPA: cullvax!drw@eddie.mit.edu
UUCP: ...!seismo!harvard!mit-eddie!cullvax!drw
If you light a match, how much mass does it convert into energy?