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Extension to MAP

    Date: Fri, 20 Mar 87 17:05 EST
    From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

	Date: 20 Mar 1987 16:24-EST

	     I'd really like to see MAP take a sequence as its first
	argument, and have the results be put into that sequence.
	     The first N elements of the sequence would be modified
	where N is the min of the lengths of the argument sequences,
	(including the sequence passed as the first arg).
	     This seems upward-compatible and easy to implement, and
	would be extremely handy.
	     Any comments?

    It sounds like a good idea, but what if the sequence is () ?

I'm not sure which objection you're making, so I'll clarify by
generalizing it twice.

1)  Generalize this to "What if the sequence is shorter than the
    number of times the mapped function would otherwise be called?"

2) Generalize this to "What if the sequence is (array t)?"

The first interpretation is a trivial design decision, but the second is
a fatal flaw in the scheme.  I suspect this is really the point you were
trying to make: some sequences already have meaning in that context.