[ZODB-Dev] __cmp__() for PersistentMapping?

[Greg Ward]

On 16 August 2001, Jim Fulton said:
> > Of course, this assumes that other is also a PersistentMapping.  Hmmm.
> 
> Hm indeed, but this is an improvement.

OK, here are two variations on the patch (relative to current CVS).  I'm
not sure which one is Zope-ologically correct; the first (isinstance) is
unreliable because isinstance() didn't work with ExtensionClass prior to
Python 2.1.  The second (hasattr) is a hack.  Take your pick, or do it
your own way, or just ignore me...

VARIATION 1:
--- PersistentMapping.py        16 Aug 2001 17:25:41 -0000      1.11
+++ PersistentMapping.py        16 Aug 2001 17:35:40 -0000
@@ -161,3 +161,5 @@
     def __cmp__(self,other):
-        return cmp(self._container, other._container)
-
+        if isinstance(other,PersistentMapping):
+            return cmp(self._container, other._container)
+        else:
+            return cmp(self._container, other)


VARIATION 2:
--- PersistentMapping.py        16 Aug 2001 17:25:41 -0000      1.11
+++ PersistentMapping.py        16 Aug 2001 17:35:51 -0000
@@ -161,3 +161,5 @@
     def __cmp__(self,other):
-        return cmp(self._container, other._container)
-
+        if hasattr(other,'_container'):
+            return cmp(self._container, other._container)
+        else:
+            return cmp(self._container, other)

        Greg