fetch urls from a url

furl.rkt

#lang racket

(require net/url)

(if (< (vector-length (current-command-line-arguments)) 1)
  (display "please define url\n")
  (display "please wait ...\n"))

(define URL (vector-ref (current-command-line-arguments) 0))
(display (string-append URL "\n"))

(let ([html (call/input-url 
              (string->url URL)
              get-pure-port
              port->string)])
  (let ([matches (regexp-match* #rx"href=\"https?://.*?\"" html)])
    (for ([m matches])
      (display (substring m 6 (- (string-length m) 1)))
      (newline))))