[test] disjunctive entailment without equality

I created a test case concerning disjunctive entailment from negative
guards that does not involve equality (and the rule is safe).  In
hindsight, it is actually kind of obvious; just an application of
DeMorgan's.  Silly that I didn't think of it before.

http://www.w3.org/2005/rules/wiki/Disjunctive_Information_from_Negative_Guards_3

With the proposed hasNotDatatype predicate you have exactly the same
issue: adding a hasNotDatatype as a conjunct to the body is equivalent
to adding hasDatatype as a disjunct to the head.


Best, Jos
-- 
Jos de Bruijn            debruijn@inf.unibz.it
+390471016224         http://www.debruijn.net/
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