Add utility actor for broadcasting messages

Author: pitr-ch

lib/concurrent/actor/utills.rb

@@ -0,0 +1,7 @@
+module Concurrent
+  module Actor
+    module Utils
+      require 'concurrent/actor/utils/broadcast'
+    end
+  end
+end

lib/concurrent/actor/utils/broadcast.rb

@@ -0,0 +1,32 @@
+require 'set'
+
+module Concurrent
+  module Actor
+    module Utils
+      class Broadcast < Context
+
+        def initialize
+          @receivers = Set.new
+        end
+
+        def on_message(message)
+          case message
+          when :subscribe
+            @receivers.add envelope.sender
+          when :unsubscribe
+            @receivers.delete envelope.sender
+          when :subscribed?
+            @receivers.include? envelope.sender
+          else
+            @receivers.each { |r| r << message }
+          end
+        end
+
+        # override to define different behaviour, filtering etc
+        def receivers
+          @receivers
+        end
+      end
+    end
+  end
+end