anchor.diff:    (prompt msg 
   	  :parser #'parse-integer
   	  :validator (or (and validator (clavier:&& (clavier:is-an-integer)
  -						    validator))
  +						    (make-validator validator)))
   			 (clavier:is-an-integer))
   	  :default default
   	  :required-p required-p
  
positive.code: 	  :error-color error-color))
  
  (defun prompt-email (&optional msg &key default 
  				     (required-p t) 
  				     if-invalid
  				     (color *prompt-color*)
  				     (error-color *prompt-error-color*))
  
negative.code: 
  (defparameter *prompt-color* nil "The default prompt color.")
  (defparameter *prompt-error-color* nil "The default error color")
  
  (defun make-validator (thing)
    (cond
      ((typep thing 'clavier:validator)
       thing)
      ((functionp thing)
       (clavier:fn thing nil))
      (t
       (error "Invalid validator spec: ~s" thing))))
  
  (defun remove-options (args &rest keys)
    (let ((args (copy-list args))
  