anchor.diff:    (:default-initargs
      :type 'string
      :message (lambda (validator object)
  -	      (format nil "~A is not a string" object)))
  +	      (declare (ignore validator))
  +	      (format nil "~S is not a string" object)))
     (:metaclass closer-mop:funcallable-standard-class))
   
   (defclass boolean-validator (type-validator)
  
positive.code:    :message (lambda (validator object)
  	      (format nil "~A and ~A"
  		      (let ((x-validator (x validator))) 
  			(funcall (message x-validator) x-validator object))
  		      (let ((y-validator (y validator)))
  			(funcall (message y-validator) y-validator object)))))
    (:metaclass closer-mop:funcallable-standard-class))
  
  (defclass one-of-validator (validator)
  
negative.code:    :message (lambda (validator object)
  	      (format nil "~A or ~A"
  		      (let ((x-validator (x validator)))
  			(validator-message x-validator object))
  		      (let ((y-validator (y validator)))
  			(validator-message y-validator object)))))
    (:metaclass closer-mop:funcallable-standard-class))
  
  (defclass or-validator (validator)
  