Trivial Prolog in Java

01: package ca.draisey.free.tprolog;
02: 
03: 
04: 
05: 
06: 
07: // -- a clause is either a binary horn clause or a simple predicate --
08: abstract class Clause extends Sentence {
09:         abstract void queryClause( final Term goal, final Variables these, final Variables goals, final Successor success );
10: 
11:         // part of the instantiation process for stripping unwanted qualifiers
12:         final Clause dequantifyClause() { return this; }
13: }
14: 
15: // fin