anchor.diff:    (print-unreadable-object (object stream :type t)
       (format stream "for ~S" (synonym-stream-symbol object))))
   
  -(defclass string-output-stream (sys.gray:fundamental-character-output-stream)
  +(defclass string-stream (sys.gray:fundamental-character-stream) ())
  +
  +(defclass string-output-stream (sys.gray:fundamental-character-output-stream
  +                                string-stream)
     ((element-type :initarg :element-type)
      (string :initarg :string))
     (:default-initargs :string nil))
  
positive.code:   (stream-element-type (shadow-stream-primary stream)))
  
  (defclass string-input-stream (sys.gray:fundamental-character-input-stream
                                 sys.gray:unread-char-mixin)
    ((string :initarg :string)
     (start :initarg :start)
     (end :initarg :end)))
  
negative.code: 
  ;;; Gray stream default methods.
  
  (defmethod stream-element-type ((stream sys.gray:fundamental-character-stream))
    'character)
  
  