anchor.diff:                ,vector ,start ,end
                 (lambda (,v ,s ,e) ,@body))))
   
  -#-(or sbcl cmu openmcl allegro)
  +#-(or sbcl cmu scl openmcl allegro)
   (progn
     ;; Stolen from f2cl.
     (defun array-data-and-offset (array)
  
positive.code:   #+sbcl
    `(sb-kernel:with-array-data ((,v ,vector) (,s ,start) (,e ,end))
       ,@body)
    #+cmu
    `(lisp::with-array-data ((,v ,vector) (,s ,start) (,e ,end))
       ,@body)
    #+openmcl
  
negative.code:              (,s (+ ,start ,offset)))
           ,@body)))
    ;; slow, copying implementation
    #-(or sbcl cmu scl openmcl allegro)
    (once-only (vector)
      `(funcall (if (adjustable-array-p ,vector)
                    #'call-with-array-data/copy
  