[Zope] Acquisition question

[Dieter Maurer]

Garito wrote at 2005-1-18 09:12 +0100:
> ...
>I would like to execute something like:
>
>object.Render(args)
>
>where:
>object is an object inside a folder inside my product
>Render is the product's Render method acquired by the object
>
>the response is the id of my product instead the id of the object as 
>expected
>
>Is this possible?

No, at least not with acquisition:

  When you acquire a method, you change its "self".

  This is necessary because the "self" of a method must
  be an instance of the class defining the method.
  The acquiring object usually does fulfill this requirement.

>How?

There are several ways:

 * you use an ExternalMethod or PythonScript for "Render"
   rather than a standard method definition

 * you make "Render" an object with a "__call__" method.
   In its "__call__" it can access the acquisition context
   (your "object" above) with "self.aq_parent".
   The product instance can be accessed with "self.aq_inner.aq_parent".

   That this works, the "Render" object's class must inherit
   from "Acquisition.[Im|Ex]plicit" and your product class
   must inherit at least from "ExtensionClass.Base" (better
   "Acquisition.[Im|Ex]plicit").

   Note that the option above is a specialization of this one
   (where you use predefined object classes with the required
   features).

 * You "reuse" the "Render" method of your product class
   in your object via:

      class MyObject(...):
        Render = MyProduct.Render.im_func
>
>Thanks a lot!
>
>

-- 
Dieter