classes with single-inheritance (not precluding multiple inheritance in a future versions
interfaces
as abstract classes (Java)
as per COM
semantics might be implementation dependent?
relationship to versioning
do we want to use the syntax:
class foo implements bar
syntax for using interfaces
syntax for declaring interfaces
the ability to export interfaces?
interfaces are related to static types
the ability to support multiple interfaces on a single class
in the COM world, interfaces offer namespace management similar to versioning
so perhaps drop versioning in favor of interfaces?
if you can declare that a class implements an imported defined interface it would make it easier to link it to external code
Question: interfaces are abstract classes and don't cost much to add once you have classes, right or wrong?
if you allow extension of interfaces, you are getting into multiple inheritance
some concerns about exporting interfaces from ECMAScript to other languages - perhaps we defer this capability for now?
we need to enable linkage into ActiveX and Java