Gestalt-based ground.rkt

minimart/ground.rkt

@@ -1,5 +1,6 @@
 #lang racket/base
 
+(require racket/set)
 (require racket/match)
 (require racket/list)
 (require "core.rkt")
@@ -12,15 +13,18 @@
 (define (event-handler descriptor)
   (handle-evt descriptor (lambda vs (send (event descriptor vs)))))
 
-(define (extract-active-events routes)
+(define event-projection (compile-gestalt-projection (event ?! ?)))
-  (filter-map (lambda (r)
+
-		(and (route-subscription? r)
+(define (extract-active-events gestalt)
-		     (zero? (route-meta-level r))
+  (define es (gestalt-project->finite-set gestalt 0 0 #f event-projection))
-		     (zero? (route-level r))
+  ;; TODO: how should the following error be handled, ideally?
-		     (match (route-pattern r)
+  ;; In principle, security restrictions should make it impossible.
-		       [(event descriptor (? wildcard?)) (event-handler descriptor)]
+  ;; But absent those, what should be done? Should an offending
-		       [_ #f])))
+  ;; process be identified and terminated?
-	      routes))
+  (when (not es) (error 'extract-active-events "User program subscribed to wildcard event"))
+  (for/list [(ev (in-set es))]
+    (match-define (vector e) ev)
+    (event-handler e)))
 
 (define idle-handler
   (handle-evt (system-idle-evt) (lambda _ #f)))
@@ -44,8 +48,8 @@
 		  (await-interrupt #f (struct-copy process p [state new-state]) active-events)]
 		 [(cons a actions)
 		  (match a
-		    [(routing-update routes)
+		    [(routing-update gestalt)
-		     (process-actions actions (extract-active-events routes))]
+		     (process-actions actions (extract-active-events gestalt))]
 		    [(quit)
 		     (log-info "run-ground: Terminating by request")
 		     (void)]