machine.rb in state_machine-0.7.2

- old
+ new

@@ -923,24 +923,43 @@
     # Creates a callback that will be invoked *before* a transition is
     # performed so long as the given requirements match the transition.
     # 
     # == The callback
     # 
-    # Callbacks must be defined as either the only argument, in the :do option,
-    # or as a block.  For example,
+    # Callbacks must be defined as either an argument, in the :do option, or
+    # as a block.  For example,
     # 
     #   class Vehicle
     #     state_machine do
     #       before_transition :set_alarm
-    #       before_transition all => :parked :do => :set_alarm
+    #       before_transition :set_alarm, all => :parked
+    #       before_transition all => :parked, :do => :set_alarm
     #       before_transition all => :parked do |vehicle, transition|
     #         vehicle.set_alarm
     #       end
     #       ...
     #     end
     #   end
     # 
+    # Notice that the first three callbacks are the same in terms of how the
+    # methods to invoke are defined.  However, using the <tt>:do</tt> can
+    # provide for a more fluid DSL.
+    # 
+    # In addition, multiple callbacks can be defined like so:
+    # 
+    #   class Vehicle
+    #     state_machine do
+    #       before_transition :set_alarm, :lock_doors, all => :parked
+    #       before_transition all => :parked, :do => [:set_alarm, :lock_doors]
+    #       before_transition :set_alarm do |vehicle, transition|
+    #         vehicle.lock_doors
+    #       end
+    #     end
+    #   end
+    # 
+    # Notice that the different ways of configuring methods can be mixed.
+    # 
     # == State requirements
     # 
     # Callbacks can require that the machine be transitioning from and to
     # specific states.  These requirements use a Hash syntax to map beginning
     # states to ending states.  For example,
@@ -1015,12 +1034,12 @@
     #   :unless => lambda {|user| user.signup_step <= 2}). The method, proc or
     #   string should return or evaluate to a true or false value. 
     # 
     # Examples:
     # 
-    #   before_transition :parked => :idling, :if => :moving?
-    #   before_transition :on => :ignite, :unless => :seatbelt_on?
+    #   before_transition :parked => :idling, :if => :moving?, :do => ...
+    #   before_transition :on => :ignite, :unless => :seatbelt_on?, :do => ...
     # 
     # === Accessing the transition
     # 
     # In addition to passing the object being transitioned, the actual
     # transition describing the context (e.g. event, from, to) can be accessed
@@ -1029,14 +1048,18 @@
     # 
     # For example,
     # 
     #   class Vehicle
     #     # Only specifies one parameter (the object being transitioned)
-    #     before_transition :to => :parked, :do => lambda {|vehicle| vehicle.set_alarm}
+    #     before_transition :to => :parked do |vehicle|
+    #       vehicle.set_alarm
+    #     end
     #     
     #     # Specifies 2 parameters (object being transitioned and actual transition)
-    #     before_transition :to => :parked, :do => lambda {|vehicle, transition| vehicle.set_alarm(transition)}
+    #     before_transition :to => :parked do |vehicle, transition|
+    #       vehicle.set_alarm(transition)
+    #     end
     #   end
     # 
     # *Note* that the object in the callback will only be passed in as an
     # argument if callbacks are configured to *not* be bound to the object
     # involved.  This is the default and may change on a per-integration basis.
@@ -1222,10 +1245,12 @@
           attribute = self.attribute
           
           # Tracks the event / transition to invoke when the action is called
           @instance_helper_module.class_eval do
             attr_writer "#{attribute}_event"
-            attr_accessor "#{attribute}_event_transition"
+            
+            protected
+              attr_accessor "#{attribute}_event_transition"
           end
           
           # Interpret non-blank events as present
           define_instance_method("#{attribute}_event") do |machine, object|
             event = object.instance_variable_get("@#{attribute}_event")