;; In Emacs, open this file in -*- Scheme -*- mode.

;; Strings

(def string?
     (fun (o)
          (and (@block? o) (= 200 (@block-tag o)))))

(def string-length
     (fun (s)
          (@block-length s)))

(def string-get
     (fun (s i)
          (@block-get s i)))

(def string-print
     (fun (s)
          (rec loop ((i 0))
               (if (< i (string-length s))
                   (begin
                     (char-print (string-get s i))
                     (loop (+ i 1)))))))

(def string-concat
     (fun (s1 s2)
          (let* ((l1 (string-length s1))
                 (l2 (string-length s2))
                 (n (+ l1 l2))
                 (s (@block-alloc-200 n)))
            (rec loop ((i 0))
                 (if (< i l1)
                     (begin
                       (@block-set! s i (@block-get s1 i))
                       (loop (+ i 1)))))
            (rec loop ((i 0))
                 (if (< i l2)
                     (begin
                       (@block-set! s (+ i l1) (@block-get s2 i))
                       (loop (+ i 1)))))
            s)))