+ ((eq? (car arg) #\w)
+ (set! session (cons '(search-mode . wait) session)))
+ ((eq? (car arg) #\x)
+ (let* ((c (assoc 'xargs session)) (p (string-index (cdr arg) #\=))
+ (recons (cons (substring (cdr arg) 0 p) (substring (cdr arg) (1+ p)))))
+ (if c (set-cdr! c (cons recons (cdr c)))
+ (set! session (cons (cons 'xargs (list recons)) session)))))