bug#20512: bogus warning with (format) and ~{ ~}

[Daniel Llorens]

Hello,

this is with current master, I don't know what stable 2.0 does, although I 
don't think it's changed there.

scheme@(guile-user)> (format #t "~{~{~a~^ ~}\n~}" '((1 2) (3 4)))
;;; <stdin>:1:0: warning: "~{~{~a~^ ~}\\n~}": wrong number of `format' 
arguments: expected 2, got 1
1 2
3 4
$1 = #t

apparently it only happens with double nesting, e.g. triple nesting is fine:

scheme@(guile-user)> (format #t "~{~{~{~a~^:~}~^ ~}\n~}" '(((1 2) (3 4)) ((5 6) 
(7 8))))
1:2 3:4
5:6 7:8
$2 = #t

Regards,

        Daniel