[racket] Counter servlet

From: Mark Carter (mcturra2000 at yahoo.co.uk)
Date: Tue Oct 12 17:29:27 EDT 2010

I thought I'd try to implement a stateful counter web app using DrRacket. Here's 
my code:

#lang racket

;;;; define a really simply counter

;;; required libraries
(require web-server/formlets

(define (counter request)
  (let ((count 0))      
    (define (response-generator embed/url)
      (set! count (+ 1 count))
      `(html (head (title "Counter"))
              (p "Computer says: " ,(number->string count))
              ,(embed/url (lambda (request)
                            (counter (redirect/get))))
              (p "Enjoy!"))))   
    (send/suspend/dispatch response-generator)))

(define log-file 
   (build-path (expand-user-path "~") 
; would this work better?:
; e.g. (list (build-path "js") (build-path "css"))

;;; Start the server
(serve/servlet counter 
               #:port 8080 
               #:listen-ip #f 
               #:log-file log-file 
               #:servlet-path "/counter.rkt")

My first question is (they'll be more in subsequent post): how do I create a 
link in the part of the code that reads
,(embed/url (lambda (request)
                            (counter (redirect/get))))

because so far my browser returns the text

Computer says: 1/counter.rkt;((%22k%22%20.%20%22(1%201%2064623065)%22))


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