AIMA.Test.Core.Unit.Logic.FOL.UnifierTest.testAdditionalVariableMixtures C# (CSharp) Method

        public void testAdditionalVariableMixtures()
        {
            FOLDomain domain = new FOLDomain();
            domain.addConstant("A");
            domain.addConstant("B");
            domain.addFunction("F");
            domain.addFunction("G");
            domain.addFunction("H");
            domain.addPredicate("P");

            FOLParser parser = new FOLParser(domain);

            // Test Cascade Substitutions handled correctly
            Sentence s1 = parser.parse("P(z, x)");
            Sentence s2 = parser.parse("P(x, a)");
            Dictionary<Variable, Term> result = unifier.unify(s1, s2);

            Assert.AreEqual("{z=a, x=a}", result.ToString());

            s1 = parser.parse("P(x, z)");
            s2 = parser.parse("P(a, x)");
            result = unifier.unify(s1, s2);

            Assert.AreEqual("{x=a, z=a}", result.ToString());

            s1 = parser.parse("P(w, w, w)");
            s2 = parser.parse("P(x, y, z)");
            result = unifier.unify(s1, s2);

            Assert.AreEqual("{w=z, x=z, y=z}", result.ToString());

            s1 = parser.parse("P(x, y, z)");
            s2 = parser.parse("P(w, w, w)");
            result = unifier.unify(s1, s2);

            Assert.AreEqual("{x=w, y=w, z=w}", result.ToString());

            s1 = parser.parse("P(x, B, F(y))");
            s2 = parser.parse("P(A, y, F(z))");
            result = unifier.unify(s1, s2);

            Assert.AreEqual("{x=A, y=B, z=B}", result.ToString());

            s1 = parser.parse("P(F(x,B), G(y),         F(z,A))");
            s2 = parser.parse("P(y,      G(F(G(w),w)), F(w,z))");
            result = unifier.unify(s1, s2);

            Assert.IsNull(result);

            s1 = parser.parse("P(F(G(A)), x,    F(H(z,z)), H(y,    G(w)))");
            s2 = parser.parse("P(y,       G(z), F(v     ), H(F(w), x   ))");
            result = unifier.unify(s1, s2);

            Assert.AreEqual(
                    "{y=F(G(A)), x=G(G(A)), v=H(G(A),G(A)), w=G(A), z=G(A)}",
                    result.ToString());
        }