In article <·············@WINTERMUTE.eagle>,
SDS <···········@cctrading.com> wrote:
>(defun zz (&optional (a t)) (format t "zz: a: ~a~%" a))
>(defun xx (&optional a) (format t "xx: a: ~a~%" a) (zz a))
>(xx)
>xx: a: nil
>zz: a: nil
>nil
>
>xx like (if a (zz a) (zz))?
>
This kludge wont help with (xx nil), but the following will:
(defun xx (&optional (a nil a-supplied?))
(format t "xx: a: ~a~%" a)
(if a-supplied?
(zz a)
(zz)))
(xx)
xx: a: NIL
zz: a: T
(xx nil)
xx: a: NIL
zz: a: NIL
--
--------------------------------------------------------------------------
Bernhard Pfahringer
Austrian Research Institute for http://www.ai.univie.ac.at/~bernhard/
Artificial Intelligence ········@ai.univie.ac.at