Simplify blocking-box's manager

blocking-box.rkt

@@ -19,8 +19,8 @@
 (define (manager s g)
   (define v (channel-get s))
   (let loop ()
-    (sync (handle-evt s (lambda (ignored-new-v) (loop)))
-	  (handle-evt (channel-put-evt g v) (lambda (dummy) (loop))))))
+    (sync s (channel-put-evt g v)) ;; ignore any future settings, answer all future gettings
+    (loop)))
 
 (define (blocking-box-evt b)
   (guard-evt

test-blocking-box.rkt

@@ -0,0 +1,10 @@
+#lang racket/base
+
+(require "blocking-box.rkt")
+(require rackunit)
+
+(define b (make-blocking-box))
+(set-blocking-box! b 1)
+(set-blocking-box! b 2)
+(set-blocking-box! b 3)
+(check-equal? (blocking-box-value b) 1)