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maplist and lists



    Date: Tue, 6 Jan 87 12:57 EST
    From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU>

	Date: Tue, 6 Jan 87 11:35 EST
	From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

	    Date: Tue, 6 Jan 87 11:07 EST
	    From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU>

	What do you want
		(maplist #'list '(1 2 3 . 4) '(a b . c) '(x y z w q r s))
	to return, and why?  What I'm asking for is your "well defined"
	definition.

    (((1 2 3 . 4) (a b . c) (x y z w q r s))
     ((2 3 . 4) (b . c) (y z w q r s))
     ((3 . 4) c (z w q r s)))

    since there are no further cdr's of the middle form that would be it!

    One can argue that
    w/o dotted lists one can continue to take cdrs (getting nil) until all lists
    are ended, but using a dotted list, you "wave" that - one of the lists
    finished, so there are no further maps to be done. Note that this is not a
    problem it might be with MAPCAR, where a lot of information might be
    (silently) lost, though the same principle could apply...

That's pretty much what I expected.  That still doesn't give an EXACT
definition.  Consider
	(maplist #'identity '(1 2 3))
vs	(maplist #'identity '(1 2 3 . nil))

One could argue the final "dotted" NIL should be explicitly passed, and
the result of both would be
	((1 2 3) (2 3) (3) NIL)
instead of the current
	((1 2 3) (2 3) (3))