marketplace-2014/examples/echo-plain.rkt

20 lines
587 B
Racket

#lang racket/base
;; Plain Racket version, using (require) instead of #lang marketplace.
(require marketplace/sugar)
(require marketplace/drivers/tcp-bare)
(define (echoer from to)
(transition/no-state
(publisher (tcp-channel to from ?))
(subscriber (tcp-channel from to ?)
(on-absence (quit))
(on-message
[(tcp-channel _ _ data)
(send-message (tcp-channel to from data))]))))
(ground-vm tcp
(observe-publishers (tcp-channel ? (tcp-listener 5999) ?)
(match-conversation (tcp-channel from to _)
(on-presence (spawn (echoer from to))))))