Alias Machine#event as Machine#on

CHANGELOG.rdoc

@@ -1,5 +1,6 @@
 == master
 
+* Alias Machine#event as Machine#on
 * Fix nil from/to states not being handled properly
 * Simplify hooking callbacks into loopbacks
 * Add simplified transition/callback requirement syntax

lib/state_machine/machine.rb

@@ -618,6 +618,9 @@ def state_for(object)
     # Defines one or more events for the machine and the transitions that can
     # be performed when those events are run.
     # 
+    # This method is also aliased as +on+ for improved compatibility with
+    # using a domain-specific language.
+    # 
     # == Instance methods
     # 
     # The following instance methods are generated when a new event is defined
@@ -705,6 +708,7 @@ def event(*names, &block)
 
       events.length == 1 ? events.first : events
     end
+    alias_method :on, :event
 
     # Creates a callback that will be invoked *before* a transition is
     # performed so long as the given requirements match the transition.

test/unit/machine_test.rb

@@ -937,6 +937,11 @@ def test_should_evaluate_block_within_event_context
     assert responded
   end
 
+  def test_should_be_aliased_as_on
+    event = @machine.on(:ignite) {}
+    assert_equal :ignite, event.name
+  end
+
   def test_should_have_events
     event = @machine.event(:ignite)
     assert_equal [event], @machine.events.to_a