Document why the clerk-act-update-loop calls itself

diff --git a/worlds/bricabrac.scm b/worlds/bricabrac.scm
index d458327d3cd72d97d45f6b0cccb0f0bde8240bef..84836fa7690ab0c19d81eeca9105f70ed3b1716d 100644 (file)
--- a/worlds/bricabrac.scm
+++ b/worlds/bricabrac.scm
@@ -674,6 +674,7 @@ attend to.\n")
 (define clerk-return-to-slacking-text
   "The desk clerk enters and slams the door behind her.\n")
 
+
 (define (clerk-act-update-loop clerk message)
   (define (tell-room text)
     (<- clerk (gameobj-loc clerk) 'tell-room
@@ -681,6 +682,14 @@ attend to.\n")
         #:exclude (actor-id clerk)))
   (define (loop-if-not-destructed)
     (if (not (slot-ref clerk 'destructed))
+        ;; This iterates by "recursing" on itself by calling itself
+        ;; (as the message handler) again.  It used to be that we had to do
+        ;; this, because there was a bug where a loop which yielded like this
+        ;; would keep growing the stack due to some parameter goofiness.
+        ;; That's no longer true, but there's an added advantage to this
+        ;; route: it's much more live hackable.  If we change the definition
+        ;; of this method, the character will act differently on the next
+        ;; "tick" of the loop.
         (<- clerk (actor-id clerk) 'update-loop)))
   (match (slot-ref clerk 'state)
     ('slacking