From 887aada203ecd4e9f96084b71e504b972481e6c8 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonygarnockjones@gmail.com>
Date: Wed, 26 Oct 2011 00:06:29 -0400
Subject: [PATCH] Break threads only after their output-queues have been
 drained.

---
 conversation.rkt | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/conversation.rkt b/conversation.rkt
index 2887bfe..cace762 100644
--- a/conversation.rkt
+++ b/conversation.rkt
@@ -156,11 +156,16 @@
 				   acc
 				   (choice-evt acc
 					       (let-values (((first rest) (dequeue (unbox qb))))
-						 (handle-evt (channel-put-evt (binding-out-ch b)
-									      first)
-							     (lambda (dummy)
-							       (set-box! qb rest)
-							       (room-main state)))))))
+						 (if (and (departed? first)
+							  (binding-break-on-departure? b))
+						     (begin (break-thread (binding-thread b))
+							    never-evt)
+						     (handle-evt (channel-put-evt
+								  (binding-out-ch b)
+								  first)
+								 (lambda (dummy)
+								   (set-box! qb rest)
+								   (room-main state))))))))
 			     (handle-evt (binding-in-ch b)
 					 (lambda (message)
 					   (room-main (handle-binding-message state b message))))
@@ -231,7 +236,4 @@
 
 (define (enqueue-message! b message)
   (define qb (binding-queue-box b))
-  (if (and (departed? message)
-	   (binding-break-on-departure? b))
-      (break-thread (binding-thread b))
-      (set-box! qb (enqueue (unbox qb) message))))
+  (set-box! qb (enqueue (unbox qb) message)))