FAQ: What's Wrong with Multiple Inheritance? (was Re: RDF Concepts Reference)

> > >> rdfs:ConstraintProperty is the only class that is a subclass of
> > >> two other classes.  Why?
> > 
> > To me it looks like an oddity in the rdf class hierarchy and is the
> > only part that means RDF schema implementations have to support
> > multiple inheritance.  Maybe this is required anyway but it isn't
> > explicitly described.  
> > 
> > If it is so clear to you Dennis, why don't you explain it?
> 
> "Multiple inheritance" in RDF is in large part forced on us by having a
> flat space of identifiers (or identifiable objects).

OK, here's a question I seem to have to ask very frequently, but to which I 
never seem to get a useful answer.  What on Earth is wrong with multiple 
inheritance?

It seems that ever since Java came out crowing for some odd reason that it had 
"fixed" C++'s use of MI, the orthodoxy has become that multiple inheritance is 
bad, but I think this is nonsense.

Certainly in RDF it makes the most eminent sense.  Inheritance is a simple 
arc, and I don't see how the cardinality of that particular arc hampers the 
quality of the expression or implementation in any way.


-- 
Uche Ogbuji                               Principal Consultant
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