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Re: New FILEPKG command: INITVARS; also RPAQ? etc.
- To: KAPLAN
- Subject: Re: New FILEPKG command: INITVARS; also RPAQ? etc.
- From: JonL.PA
- Date: Sun, 13 Jun 1982 23:12:15 -7000
- Date: 13 June 1982 11:12 pm PDT (Sunday)
- Cc: lispcore^, lisp
- In-reply-to: KAPLAN's message of 12 JUN 1982 1522-PDT
One thing that has to be considered about this feature is how to load "patch"
files so that the INITVARS vars *do* get reset; the LISPM people have some
trivial little thing to override the non-reSETting nature of a CommonLisp
DEFVAR when a "patch" file is loaded, and I don't remember exactly how it
works, but I'm sure almost any little trick will do once the problem is faced.
Re RPAQ? (which looks equivalent to the MacLisp SETQ-IF-UNBOUND), I've
often wanted yet a third version of SETQ which does the setqing only if the
value is non-null (but returns the value obtained regardless). See example
I've also heard lots of other people complain about Lisp's lack of "pronouns" a la
the "IT" of lispx; SETQ-if-non-null catches some high percentages of these
cases. Lack of "pronouns" means that you often see code like
(IF (GET X 'FROBULATE) THEN (PRINT (GET X 'FROBULATE)))
where you'd like to write
(IF (GET X 'FROBULATE) THEN (PRINT it))
Example use of SETQ-IF-VALUE-NON-NULL:
((SETQ.IFNN WHATTODO (FIND.MORE.WORK))
((ASKUSER ...if I should just try "polishing-up" the old some more ...)
(T (GO AROUNDLOOP)))