The type of the object to return by reference.
If non-
nil
, if the input argument is
nil
a null pointer is passed instead of a reference to an object containing
nil
.
The FLI
:reference-return
type is a shorthand for
:reference with
lisp-to-foreign-p
set to
nil
and
foreign-to-lisp-p
set to
t
. See :reference for more details.