(define char-control-1?
  (lambda (ch)
    (if (and (<= 0 (char->integer ch))
             (< (char->integer ch) 32))
        #t
        (if (eq? (char->integer ch) 127)
            #t
            #f))))

(define char-control-2?
  (lambda (ch)
    (if (and (<= 0 (char->integer ch))
             (< (char->integer ch) 32))
        #t
        (if (eq? (char->integer ch) 127)
            #t
            #f))))