anchor.diff:    (let ((primaries (remove-if-not #'primary-method-p methods))
           (around (find-if #'around-method-p methods)))
       (when (null primaries)
  -      (error "No primary methods for the~@
  -             generic function ~S." gf))
  +      (error "No primary methods for the generic function ~S. Called with " gf))
       (if around
           (let ((next-emfun
                   (funcall
  
positive.code:     (character                                     (find-class 'character))
      (hash-table                                    (find-class 'hash-table))
      (package                                       (find-class 'package))
      ;;(pathname                                      (find-class 'pathname))
      ;;(readtable                                     (find-class 'readtable))
      (synonym-stream                                (find-class 'synonym-stream))
      (stream                                        (find-class 'stream))
  
negative.code:   (let* ((classes (mapcar #'class-of
                            (required-portion gf args)))
           (applicable-methods
            (compute-applicable-methods-using-classes gf classes)))
      (when (null applicable-methods)
        (error "No applicable methods to generic function ~S.
  Dispatching on class ~S." gf class))
      (let ((emfun (std-compute-effective-method-function gf applicable-methods)))
        (setf (gethash class (classes-to-emf-table gf)) emfun)
        (funcall emfun args))))
  
  ;;; compute-applicable-methods-using-classes
  
  