[Zope] Inheritance (?) problem

[Luca Manini]

>>>>> "Dieter" == Dieter Maurer <dieter@handshake.de> writes:

    > Luca Manini writes:
    [...]

    When overriding a superclass (base) method (foo) in a subclass
    (sub), one often wants to call the inherited one. In 'pure'
    (bare?) Python you can do this:

    class sub (base):
	def foo(self, arg): 
            sub.foo (self, arg)

    I tried this with sub inheriting from SimpleItem.SimpleItem and
    from an external 'pure python' class and it does not work.

    > This is an ExtensionClass/Python incompatibility, documented
    > with ExtensionClass. You need "inheritedAttribute" to work
    > around the problem, documented too.
    > Dieter

    As always, Dieter (thanks) solved the problem! .

    1) documented means (I think) read 

	..../zope/lib/python/StructuredText/regressions/ExtensionClass.stx

       funny place for that piece of really interesting info. 

    2) You need inheritedAttribute means (I do that way and it works):

	class sub (base):
	    def foo(self, arg): 
                sub.inheritedAttribute ('foo') (self, arg)

       Any other trick like this in constructing (product's) Zope
       classes from 'pure-python' ones?

       I do prefere to have as much python code as possible out of
       Zope (so that it can be use without Zope), and overriding
       inherited methods is (I think) a very basic tool in this.


	bye, Luca