anchor.diff:  (defun pass1-jump-table (form env)
     (destructuring-bind (test-form &body forms) (cdr form)
       (make-instance 'ast-jump-table
  +                   :optimize (optimize-qualities-in-environment env)
                      :value (pass1-form test-form env)
                      :targets (pass1-implicit-progn forms env))))
  
positive.code:   (destructuring-bind (functions &body forms) (cdr form)
      (multiple-value-bind (body declares)
          (parse-declares forms)
        (let ((bindings '()))
          (make-instance 'ast-let
                         :bindings (mapcar (lambda (x)
                                             (multiple-value-bind (sym var lambda)
                                                 (frob-flet-function x)
  
negative.code:            (pass1-variable form env))))
      ;; Self-evaluating forms are quoted.
      ((not (consp form))
       (make-instance 'ast-quote
                      :optimize (optimize-qualities-in-environment env)
                      :value form))
      ;; ((lambda ...) ...) is converted to (funcall #'(lambda ...) ...)
      ((and (consp (first form))
            (eq (first (first form)) 'lambda))
  