On 22 July 2011 13:32, Joshua Immanuel <j...@hipro.co.in> wrote: > Hello, > > On Fri, 2011-07-22 at 13:41 +0200, Jacob Holm wrote: >> On 2011-07-22 13:26, Brian Sutherland wrote: >> > This would be my first guess: >> > >> > class INode(Interface): >> > pass >> > >> > INode.parent = Object( >> > title=u"Parent node", >> > schema=INode >> > ) >> > >> > INode.children = List( >> > title=u'Child nodes', >> > value_type=Object(schema=INode) >> > ) >> > >> > > The method suggested by Brian works without any issues. :)
No, there are issues. Take this example: >>> class ITest(Interface): ... title = schema.TextLine() ... >>> ITest.names <bound method InterfaceClass.names of <InterfaceClass __main__.ITest>> >>> ITest.names() ['title'] >>> ITest.description = schema.Text() >>> ITest.names() ['title'] The fields on an interface are not stored as attributes, but are accessible using item access, e.g: ITest['title']. You cannot assign that way though: >>> ITest['description'] = schema.TextLine() Traceback (most recent call last): File "<console>", line 1, in <module> TypeError: 'InterfaceClass' object does not support item assignment Adding to an interface requires messing with the '_InterfaceClass__attrs' attribute of the dictionary and is discouraged. Laurence _______________________________________________ Zope-Dev maillist - Zope-Dev@zope.org https://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope )
