(multiple-value-bindf (class home foreign)
(meta-model:explode-has-many instance (slot-name slot))
(let ((new (make-instance class)))
(setf (slot-value new foreign) (slot-value instance home))
(meta-model:sync-instance new :fill-gaps-only-p (fill-gaps-only-p self))
(multiple-value-bindf (class home foreign)
(meta-model:explode-has-many instance (slot-name slot))
(let ((new (make-instance class)))
(setf (slot-value new foreign) (slot-value instance home))
(meta-model:sync-instance new :fill-gaps-only-p (fill-gaps-only-p self))