Question about MzScheme Objects

["Alex Peake" <apeake@comac.com>]

I define:

(define attr<%> (interface () set-name! pk? set-pk!))

(define attr%
  (class* object% (attr<%>) (attr-name (pk #f) (fk #f))
    (public
      (domain 'integer)
      (name attr-name)
      (set-name! (lambda (attr-name) (set! name attr-name)))
      (pk? (lambda () pk))
      (set-pk! (lambda (is-pk) (set! pk is-pk)))
      (fk? (lambda () fk)))
    (sequence (super-init))))

1) why is there an instance variable fk (and not an instance variable
attr-name)(or maybe there is)?

2) is there a way to default pk and yet set fk?

3) why is fk? not required in the interface?


Thanks,

Alex