v2ex619370.rkt

#lang racket
;;; Solve <https://www.v2ex.com/t/619370>

(define (get-group ipaddr lines)
  (define group-name null)
  (let/cc return
    (map (λ (line)
           (cond
             [(parse-group-name line)
              => (λ (parsed-group-name)
                   (set! group-name parsed-group-name))]
             [(equal? (parse-host-name line) ipaddr)
              (return group-name)]))
         lines)))

(define (parse-group-name line)
  (if (eq? (car line) 'object-group)
      (caddr line)
      #f))

(define (parse-host-name line)
  (if (eq? (car line) 'network-object)
      (caddr line)
      #f))

(define lines
  '((network-object host 109.17.49.131)
    (object-group network KaGuan_12)
    (network-object host 109.17.26.11)
    (network-object host 109.17.26.12)
    (object-group network ShangHai)
    (network-object host 110.1.60.91)
    (network-object host 110.1.60.92)
    (network-object host 110.1.172.31)
    (network-object host 110.1.172.32)
    (network-object host 110.238.250.57)
    (network-object host 110.238.250.58)
    (object-group network wangguan_test)
    (network-object host 111.17.13.32)
    (object-group network wangguan_app_2)
    (network-object host 111.17.9.54)
    (network-object host 111.17.9.63)))

(get-group '110.1.172.32 lines)