Changeset 5475:eb192c62bc10 for sage/categories/action.pyx

Timestamp:

07/12/07 22:06:46 (6 years ago)

Author:

Robert Bradshaw <robertwb@…>

Branch:

default

Message:

action coercion tweaks

File:

• sage/categories/action.pyx (modified) (1 diff)

sage/categories/action.pyx

@@ -130 +130 @@
     """
     def __init__(self, Action action):
-        Action.__init__(action._G, action._S, action._is_left)
-        self._action = action
+        G = action._G
+        try:
+            from sage.groups.group import Group
+            if (PY_TYPE_CHECK(G, Group) and G.is_multiplicative()) or G.is_field():
+                Action.__init__(self, G, action._S, action._is_left)
+                self._action = action
+        except AttributeError:
+            pass
+        raise TypeError, "No inverse defined for %r." % action
         
     cdef Element _call_c(self, a, b):