[Zope-CMF] isinstance on ActionProviderBase

[Nicolas Romero]

Hi,

I am developping a product and I have a problem using isinstance on
ActionProviderBase objects. Here is an excerpt of my code :

## start here
from Products.CMFCore.ActionProviderBase import ActionProviderBase
from AccessControl.Role import RoleManager

 def getObjectConfigFromZope( self, obj):
      d = {} 
      if isinstance( obj, RoleManager):
            d['permissions'] = self.getPermissions( obj)
            d['localroles'] = self.getLocalroles( obj)
       if isinstance( obj, ActionProviderBase):
            d['actions'] = self.getActions( obj)
## end here

Let obj be a CMF tool, for example portal_types, of class TypesTool,
which is defined as 

class TypesTool( UniqueObject, OFS.Folder.Folder, ActionProviderBase ):

I don't understand why isinstance(obj,RoleManager) returns 1 [correct],
isinstance( obj,ActionProviderBase) returns 0 [why ?]. If I replace the
latter with issubclass(obj.__class__,ActionProviderBase), it returns 1
[correct].

On the other hand, in Python, I obtain :

$ python
Python 2.1.3 (#1, Jun 11 2003, 11:49:07)
[GCC 2.95.4 20011002 (Debian prerelease)] on linux2
Type "copyright", "credits" or "license" for more information.
>>> class A:
...   pass
...
>>> class B(A):
...   pass
...
>>> class C:
...   pass
...
>>> class D(C,A):
...   pass
...
>>> b = B()
>>> isinstance(b, A)
1
>>> d=D()
>>> isinstance(d,A)
1
>>> issubclass(d.__class__,A)
1
>>>

What is the difference between d and obj ?

-- 
Nicolas Romero, adp3i - 101, rue Bannier 45000 ORLEANS
                     |
Tél: 02 38 81 06 47  | adp3i <http://www.adp3i.fr>
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