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Re: Subclass

Sorry, that doesn't do what I need.

I have an object (call it F) of class foo and an object of class foo-bar (call it FB).

class foo-bar is a sub-class of foo.
class foo does implement some methods but would like to leave others to the sub-classes.

Another object (call it test) would like to call methods on objects of super-class type foo. However, foo is never instantiated, only subclasses are. Also, I'd like to have foo declare some methods that it doesn't implement but I would like to guarantee sub-classes implement. Protocols aren't that strict.

Please correct me if I'm wrong here.`

Protocols produce compiler warnings if your class doesn't comply. Your superclass can include the protocols, and all subclasses inherit them. Thus, if someone defines a subclass which doesn't meet the protocol requirements, it will compile, but with warnings.

Alternatively, you can just have your superclass implement the methods, but throw up an error if they're ever actually called. Not as good as a compiler warning, though.

Perhaps I still don't understand how strict you want your implementation to be, but I would say if someone ignores a compiler warning, the consequences are their's and their's alone.

Wade Tregaskis
-- Sed quis custodiet ipsos custodes?
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