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Re: Are "destructive" functions really destructive?

In article <31810@news.Think.COM> barmar@think.com writes:
>If you want a DELETEF macro, create one.  This would be just like the
>distinction between 1+ and INCF.  If you think DELETEF should have been
>included in the standard language as INCF was, that's a completely
>different issue.  I suspect it wasn't because then the language would have
>had to have SETF-like versions of all the destructive sequence operations.
>Maclisp and Zetalisp, the primary influences on Common Lisp, had INCF, so
>it was kept, but the CL designers apparently didn't want to throw in a
>zillion new macros of that type.

Yeah, but don't define DELETEF on a Symbolics or you'll redefine the
GLOBAL symbol DELETEF which is used to delete files!  I did this once
a couple of years ago and spent several hours trying to figure out
why the system was acting so funny.


P.S. Barry also pointed out in another posting that I made the faulty
assumption that BACKQUOTE would create new lists.  He's right.  I goofed.
(responsible-p ADS message)