public void testNOTSentence()
{
FOLDomain domain = new FOLDomain();
domain.addConstant("A");
domain.addConstant("B");
domain.addConstant("C");
domain.addFunction("Plus");
domain.addPredicate("P");
FOLParser parser = new FOLParser(domain);
Sentence s1 = parser.parse("NOT(P(A))");
Sentence s2 = parser.parse("NOT(P(A))");
Dictionary<Variable, Term> result = unifier.unify(s1, s2);
Assert.IsNotNull(result);
Assert.AreEqual(0, result.Count);
s1 = parser.parse("NOT(P(A))");
s2 = parser.parse("NOT(P(B))");
result = unifier.unify(s1, s2);
Assert.IsNull(result);
s1 = parser.parse("NOT(P(A))");
s2 = parser.parse("NOT(P(x))");
result = unifier.unify(s1, s2);
Assert.IsNotNull(result);
Assert.AreEqual(1, result.Count);
Assert.AreEqual(new Constant("A"), result[new Variable("x")]);
}