1. (define (is-user-func? token)
  2.   (define (search list)
  3.     (cond ((null? list) #f)
  4.           ((string=? (get-name token) (get-name (car list)))
  5.            (get-name token))
  6.           (else (search (cdr list)))
  7.           )
  8.     )
  9.   (search user-funcs)
  10.   )