anchor.diff:    (:documentation
      "Result of a failed equal assertion."))
   
  -(defun equal-result (test expected actual)
  +(defmethod assert-result ((type (eql :equal)) test expected actual)
     "Return the result of an equal assertion."
     (and
      (<= (length expected) (length actual))
  
positive.code:   (:documentation
     "Result of a failed error assertion."))
  
  (defun error-result (test expected actual)
    "Return the result of an error assertion."
    (declare (ignore test))
    (or
  
negative.code:   `(lambda ()
       (list ,@(mapcan (lambda (form) (list `',form form)) extras))))
  
  (defgeneric assert-result (type test expected actual)
    (:documentation
     "Return the result of the assertion."))
  
  (defclass failure-result ()
    ((form
      :initarg :form
  