[Zope] metal Macros from PageTemplateFiles?

[Dieter Maurer]

Robert Casties wrote at 2005-1-19 14:29 +0100:
>Is it possible (and how?) to use a procedure in a product to produce a 
>PageTemplate that defines a macro, that can be used in another PageTemplate?
>
>I tried:
>
>   class SomeClass(Folder):
>
>     content_template = PageTemplateFile("/some/file/template.zpt")
>
>and the direct ssignment to a variable works, but it is not exactly what 
>I need (I need to check with the actual instance).
>
>But when I try to do:
>
>     def content_template(self):
>	pt = PageTemplateFile("/some/file/template.zpt")
>	return pt
>
>then the procedure is never called and I get an error in the ZPT that 
>tries to use the macro:
>
>   Error Type: AttributeError
>   Error Value: content_templatemacros

Two errors:

 1. as Tino already pointed out: you forgot the ".__of__(self)"

 2. you must call your "content_template" method (contrary to your
    "content_template" attribute).

    The easiest way would be a "ComputedAttribute", something like

        from ComputedAttribute import ComputedAttribute

	...
	def content_template(self):
	    ...

	content_template = ComputedAttribute(content_template, 1)

>Somewhere I read a vage reference to invoke "cook" but I don't know how.

PageTemplates get automatically "cook"ed, when necessary.

-- 
Dieter