combining ~{ with v paramaters in format string

[Ernest Adrogué]

Hi,

I'm having a little trouble with a format string, using the "format"
module.  The following two lines produce the same output: "a b".

(format #t "~a ~a~%" "a" "b")
(format #t "~{~a ~a~%~}" '("a" "b"))

Now the same thing but adding an argument to give the length of the
first element:

(format #t "~va ~a~%" 6 "a" "b")
(format #t "~{~va ~a~%~}" '(6 "a" "b"))

The first one works as expected, it prints "a      b", whereas the
second one doesn't, it says "error in format".

Is it not possible to use ~{ together with parameters given as
arguments?

Cheers.