Hi Dieter,
"Interfaces" are rarely used in Zope2 (there are a few exceptions, e.g. the "pluggable indexes" of the ZCatalog).
But in Zope3, they will be fundamental for plugging components together...
Ok, but that begs the question: are Interfaces architecturally significant, or is their utility retricted to providing a mechanism for documenting classes? I realized last night that my confusion about this was not only because of the superficial resemblance between interfaces/components and C++ abstract classes, but also because of COM: "interface," "Component," and the notion of querying an interface are core concepts in the COM architecture. But, again, unless I missed something, I did not see anything in the Interface documentation that would lead me to believe that Interfaces in Zope are anything more than a documentation mechanism. Thanks for your help! Regards, Phil