Changed event system to allow more advance listener.

See associated test for example.

papers/events.py

@@ -1,4 +1,4 @@
-_listener = {}
+_listener = []
 
 
 class Event(object):
@@ -9,16 +9,14 @@ class Event(object):
         """ This function sends the instance of the class, i.e. the event
         to be sent, to all function that listen to it.
         """
-        if self.__class__ in _listener:
+        for cls, f, args in _listener:
-            for f, args in _listener[self.__class__]:
+            if isinstance(self, cls):
                 f(self, *args)
 
     @classmethod
     def listen(cls, *args):
         def wrap(f):
-            if cls not in _listener:
+            _listener.append((cls, f, args))
-                _listener[cls] = []
-            _listener[cls].append((f, args))
 
             # next step allow us to call the function itself without Event raised
             def wrapped_f(*args):

tests/test_events.py

@@ -23,6 +23,17 @@ class AddEvent(Event):
         return a + b
 
 
+class Info(Event):
+    def __init__(self, info):
+        self.info = info
+
+
+class SpecificInfo(Info):
+    def __init__(self, info, specific):
+        Info.__init__(self, info)
+        self.specific = specific
+
+
 @TestEvent.listen(12, 15)
 def display(TestEventInstance, nb1, nb2):
     _output.append("%s %s %s"
@@ -44,6 +55,13 @@ def do_it(AddEventInstance):
     _output.append(AddEventInstance.add(17, 25))
 
 
+@Info.listen()
+def test_info_instance(infoevent):
+    _output.append(infoevent.info)
+    if isinstance(infoevent, SpecificInfo):
+        _output.append(infoevent.specific)
+
+
 class TestEvents(TestCase):
 
     def setUp(self):
@@ -64,3 +82,9 @@ class TestEvents(TestCase):
         addevent.send()
         correct = [42]
         self.assertEquals(_output, correct)
+
+    def test_listen_Info(self):
+        Info('info').send()
+        SpecificInfo('info', 'specific').send()
+        correct = ['info', 'info', 'specific']
+        self.assertEquals(_output, correct)