anchor.diff:    (find-account username))
   
   (defun confirm-password (account input)
  -  (string= (password-hash account)
  -           (hash-password input)))
  +  (when (string= (password-hash account)
  +                 (hash-password input))
  +    account))
   
   (defun/cc maybe-login (client)
     (let* ((username (prompt-client client "~&Username: "))
  
positive.code:     (if account
          (progn
            (setf (soul client) (make-instance 'soul :account account :client client))
            #+nil(format client "~&You are now logged in as ~A.~%" (username (account (soul client))))
            (format client "~&Commands: 'look' and 'quit'. Type anything else to chat.~%")
            #+nil(broadcast-to-room client "~&~A enters the world.~%" (username (account (soul client)))))
          (progn
            (format client "~&Wrong password.~%")
            (maybe-login client)))))
  
negative.code:     (if k
          (progn (setf (client-continuation client) nil)
                 (funcall k (last-input client)))
          (funcall (client-main client) client))))
  
  (defmethod teardown ((client tcp-client))
    (close client :abort t)
  