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

        public void testCascadedOccursCheck()
        {
            FOLDomain domain = new FOLDomain();
            domain.addPredicate("P");
            domain.addFunction("F");
            domain.addFunction("SF0");
            domain.addFunction("SF1");
            FOLParser parser = new FOLParser(domain);

            Sentence s1 = parser.parse("P(SF1(v2),v2)");
            Sentence s2 = parser.parse("P(v3,SF0(v3))");
            Dictionary<Variable, Term> result = unifier.unify(s1, s2);

            Assert.IsNull(result);

            s1 = parser.parse("P(v1,SF0(v1),SF0(v1),SF0(v1),SF0(v1))");
            s2 = parser.parse("P(v2,SF0(v2),v2,     v3,     v2)");
            result = unifier.unify(s1, s2);

            Assert.IsNull(result);

            s1 = parser
                    .parse("P(v1,   F(v2),F(v2),F(v2),v1,      F(F(v1)),F(F(F(v1))),v2)");
            s2 = parser
                    .parse("P(F(v3),v4,   v5,   v6,   F(F(v5)),v4,      F(v3),      F(F(v5)))");
            result = unifier.unify(s1, s2);

            Assert.IsNull(result);
        }