Hello World client in Racket

#lang racket
#|
# Hello World client in Racket
# Connects REQ socket to tcp://localhost:5555
# Sends "Hello" to server, expects "World" back
|#
(require net/zmq)

; Prepare our context and sockets
(define ctxt (context 1))
(define sock (socket ctxt 'REQ))

(printf "Connecting to hello world server…\n")
(socket-connect! sock "tcp://localhost:5555")

; Do 10 requests, waiting each time for a response
(for ([request (in-range 10)])
(printf "Sending request ~a…\n" request)
(socket-send! sock #"Hello")

; Get the reply.
(define message (socket-recv! sock))
(printf "Received reply ~a [~a]\n" request message))

(context-close! ctxt)