From 38c6bfd20e51b09cc0fdcf723f73e408161df15e Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonygarnockjones@gmail.com>
Date: Tue, 1 May 2018 17:34:51 +0100
Subject: [PATCH] Drain multiple external ground events at once. (Good or bad
 idea?)

---
 syndicate/ground.rkt | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/syndicate/ground.rkt b/syndicate/ground.rkt
index d7e7591..ea51cd5 100644
--- a/syndicate/ground.rkt
+++ b/syndicate/ground.rkt
@@ -40,14 +40,24 @@
     (define ground-event-relay-actor #f)
     (define background-activity-count 0)
 
+    (define (handle-ground-event-item item)
+      (match item
+        [(? procedure? proc)
+         (push-script! ground-event-relay-actor
+                       (lambda () (proc ground-event-relay-actor)))]
+        [(? number? delta)
+         (set! background-activity-count (+ background-activity-count delta))]))
+
+    (define (drain-external-events)
+      (define item (async-channel-try-get ch))
+      (when item
+        (handle-ground-event-item item)
+        (drain-external-events)))
+
     (define ground-event-relay-evt
       (handle-evt ch (lambda (item)
-                       (match item
-                         [(? procedure? proc)
-                          (push-script! ground-event-relay-actor
-                                        (lambda () (proc ground-event-relay-actor)))]
-                         [(? number? delta)
-                          (set! background-activity-count (+ background-activity-count delta))]))))
+                       (handle-ground-event-item item)
+                       (drain-external-events))))
 
     (define ds (make-dataspace
                 (lambda ()