[Zope3-dev] Constraining where objects can be added

[Michał Węgrzynek]

Hello!

I've got some problems with constraining where my content objects can be 
added. The example in the zope book
(http://dev.zope.org/Wikis/DevSite/Projects/ComponentArchitecture/Zope3Book/contentobject.html) 
I used doesn't work also.
Is this a bug, or the apis changed?

Here is my code:

8<-----------------------------------------------------------------------------
# -*- encoding: UTF-8 -*-
__doc__ = """An IArtist interface"""
#------------------------------------------------------------------------------
import zope.interface as zi
import zope.schema as zs
import zope.app.container.interfaces as zci
import zope.app.container.constraints as zcc
#------------------------------------------------------------------------------
class IArtist(zi.Interface):
     name = zs.TextLine(title = u"Name",
                        description = u"Artist's name",
                        required = True,
                        default = u"New")

     description = zs.Text(title = u"Description",
                           description = u"Few words about artist",
                           default = u"")

     picture = zs.Bytes(title = u"Picture",
                        description = u"Artist's picture")

     homepage = zs.TextLine(title = u"Homepage",
                            description = u"Artist's homepage",
                            required = False,
                            default = u"")
#------------------------------------------------------------------------------ 

class IArtistsContainer(zci.IContainer):
     def __setitem__(name, object):
         """Adds a IArtistsContainer object."""

     __setitem__.precondition = zcc.ItemTypePrecondition(IArtist)
#------------------------------------------------------------------------------ 

IArtist.__parent__ = zs.Field(constraint = \ 
zcc.ContainerTypesConstraint(IArtistsContainer)) # <-- This line
# supposed to allow adding artist only in ArtistsContainer
#------------------------------------------------------------------------------

Thanks for help in advance,

Michał