On Thu 26 Aug 2010 04:17, "Eric J. Van der Velden"
<[email protected]> writes:
> I don't understand what the manual says about when there are more then two
> arguments to map or for-each.
>
> With two arguments, the last one must be a list, so OK is
>
> (for-each display '(1 3))
Consider:
(map + '(1 3))
= (list (+ 1) (+ 3))
= (list 1 3)
=> (1 3)
(map + '(1 3) '(5 7))
= (list (+ 1 5) (+ 3 7))
= (list 6 10)
=> (6 10)
After the function, all args need to be lists. The `display' example you
gave, even if you had given for-each lists, still doesn't make sense:
(for-each display '(1 3) '(5 7))
= (begin (display 1 5) (display 3 7))
=> ERROR: in (display 1 5): 5 is not a port
Hope that helps,
Andy
--
http://wingolog.org/
