Add bin and edit workflow

bin/gems/eventmachine-1.2.7/lib/em/channel.rb

@@ -0,0 +1,69 @@
+module EventMachine
+  # Provides a simple thread-safe way to transfer data between (typically) long running
+  # tasks in {EventMachine.defer} and event loop thread.
+  #
+  # @example
+  #
+  #  channel = EventMachine::Channel.new
+  #  sid     = channel.subscribe { |msg| p [:got, msg] }
+  #
+  #  channel.push('hello world')
+  #  channel.unsubscribe(sid)
+  #
+  #
+  class Channel
+    def initialize
+      @subs = {}
+      @uid  = 0
+    end
+
+    # Return the number of current subscribers.
+    def num_subscribers
+      return @subs.size
+    end
+
+    # Takes any arguments suitable for EM::Callback() and returns a subscriber
+    # id for use when unsubscribing.
+    #
+    # @return [Integer] Subscribe identifier
+    # @see #unsubscribe
+    def subscribe(*a, &b)
+      name = gen_id
+      EM.schedule { @subs[name] = EM::Callback(*a, &b) }
+
+      name
+    end
+
+    # Removes subscriber from the list.
+    #
+    # @param [Integer] Subscriber identifier
+    # @see #subscribe
+    def unsubscribe(name)
+      EM.schedule { @subs.delete name }
+    end
+
+    # Add items to the channel, which are pushed out to all subscribers.
+    def push(*items)
+      items = items.dup
+      EM.schedule { items.each { |i| @subs.values.each { |s| s.call i } } }
+    end
+    alias << push
+
+    # Fetches one message from the channel.
+    def pop(*a, &b)
+      EM.schedule {
+        name = subscribe do |*args|
+          unsubscribe(name)
+          EM::Callback(*a, &b).call(*args)
+        end
+      }
+    end
+
+    private
+
+    # @private
+    def gen_id
+      @uid += 1
+    end
+  end
+end