[Zope3-checkins] CVS: Zope3/src/zope/interface - declarations.py:1.21

[Jim Fulton]

Update of /cvs-repository/Zope3/src/zope/interface
In directory cvs.zope.org:/tmp/cvs-serv13293/src/zope/interface

Modified Files:
	declarations.py 
Log Message:
Added an exception handler for access to __bases__ to give a more
informative error when trying to get implements declarations for non
classes.


=== Zope3/src/zope/interface/declarations.py 1.20 => 1.21 ===
--- Zope3/src/zope/interface/declarations.py:1.20	Fri Feb 20 11:56:50 2004
+++ Zope3/src/zope/interface/declarations.py	Mon Apr  5 15:43:59 2004
@@ -332,8 +332,12 @@
         spec.inherit = None    # old-style implies no inherit
         del cls.__implements__ # get rid of the old-style declaration
     else:
-        spec = Implements(
-            *[implementedBy(c) for c in cls.__bases__])
+        try:
+            bases = cls.__bases__
+        except AttributeError:
+            raise TypeError("ImplementedBy called for non-type", cls)
+
+        spec = Implements(*[implementedBy(c) for c in bases])
         spec.inherit = cls
 
     spec.__name__ = getattr(cls, '__module__', '?') + '.' + cls.__name__