[Zope] ComputedAttribute
Gabriel Genellina
gagenellina@softlab.com.ar
Tue, 29 Jan 2002 21:31:34 -0300
Hi
What's a "ComputedAttribute"???
I've done my work looking everywhere... Neither the Zope Book nor other
documents say nothing about it. In Dieter Maurer's book they're menctioned
but no details.
Searching at zope.org and the mailing list archives, I've just found a few
references ("a ComputedAttribute is useful here" or things like that), but
nobody says what a C.A. really is.
Looking at the Zope sources I've found a few modules using it. I guess a
ComputedAttribute acts like an instance attribute but really it's
implemented as a method. That would be useful for delegation. But in
DTMLFile class:
def _get__roles__(self):
... compute something and return that...
__roles__ = ComputedAttribute(_get__roles__, 1)
what's the second argument?
And, what's the difference with using __getattr__()?
Gabriel Genellina
Softlab SRL