APPEND

[Jonathan Rees <Rees at YALE>]

I agree completely with Drew's arguments about APPEND, although,
diplomatically, I would probably agree to support a copying version
(what to call it?  COPY-APPEND ?).  I believe that one generally knows
that the result of APPEND isn't going to be RPLAC'ed.  I personaly have
NEVER been screwed by shared structure, but I'd be willing to grant that
my coding and debugging styles are atypical.

If COPY-LIST isn't in the manual, it's a bug.  (COPY-LIST list) returns
a "top-level" copy of list, like (APPEND list '()) would in Lisp.
T makes no guarantee that (APPEND list '()) will copy the list.
(This should obviously be in the manual.)