+(defun struct-copier-structure-class (function)
+ (let ((self (sb-vm::%simple-fun-self function)))
+ (cond
+ ((member self (list *struct-copier*))
+ (find-class
+ (sb-kernel::classoid-name
+ (sb-kernel::layout-classoid
+ (sb-kernel:%closure-index-ref function 0)))))
+ )))
+