storyboard: fix Event calling get_e_id always

This fixes the behaviour of the Event class which would always
call get_e_id and fail if the action is a pure function or
not the method of a SBEntity. Now it will simply output a warning
if the event is written (because it won't be readable as-is)

On top of that, all DIFs are now scriptable, and some small fixes
and cleanups.

1 files changed, 4 insertions, 0 deletions

diff --git a/rumba/elements/topology.py b/rumba/elements/topology.py
index 3054782..c47d541 100644
--- a/rumba/elements/topology.py
+++ b/rumba/elements/topology.py
@@ -35,6 +35,10 @@ class DIF(object):
     """
     Base class for DIFs.
     """
+
+    def get_e_id(self):
+        return "DIF." + self.name
+
     def __init__(self, name, members=None):
         """
         :param name: Name of the DIF.