/YieldProlog/Modules/Functor1.cs

/*

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using System;

using System.Collections.Generic;



namespace OpenSim.Region.ScriptEngine.Shared.YieldProlog

{

    public class Functor1 : IUnifiable

    {

        public readonly Atom _name;

        public readonly object _arg1;



        public Functor1(Atom name, object arg1)

        {

            _name = name;

            _arg1 = arg1;

        }



        public Functor1(string name, object arg1)

            : this(Atom.a(name), arg1)

        {

        }



        // disable warning on l1, don't see how we can

        // code this differently

        #pragma warning disable 0168, 0219

        /// <summary>

        /// If arg is another Functor1, then succeed (yield once) if this and arg have the

        /// same name and the functor args unify, otherwise fail (don't yield).

        /// If arg is a Variable, then call its unify to unify with this.

        /// Otherwise fail (don't yield).

        /// </summary>

        /// <param name="arg"></param>

        /// <returns></returns>

        public IEnumerable<bool> unify(object arg)

        {

            arg = YP.getValue(arg);

            if (arg is Functor1)

            {

                Functor1 argFunctor = (Functor1)arg;

                if (_name.Equals(argFunctor._name))

                {

                    foreach (bool l1 in YP.unify(_arg1, argFunctor._arg1))

                        yield return false;

                }

            }

            else if (arg is Variable)

            {

                foreach (bool l1 in ((Variable)arg).unify(this))

                    yield return false;

            }

        }

        #pragma warning restore 0168, 0219





        public override string ToString()

        {

            return _name + "(" + YP.getValue(_arg1) + ")";

        }



        public bool termEqual(object term)

        {

            term = YP.getValue(term);

            if (term is Functor1)

            {

                Functor1 termFunctor = (Functor1)term;

                return _name.Equals(termFunctor._name) && YP.termEqual(_arg1, termFunctor._arg1);

            }

            return false;

        }



        public bool lessThan(Functor1 functor)

        {

            // Do the equal check first since it is faster.

            if (!_name.Equals(functor._name))

                return _name.lessThan(functor._name);



            return YP.termLessThan(_arg1, functor._arg1);

        }



        public bool ground()

        {

            return YP.ground(_arg1);

        }



        public void addUniqueVariables(List<Variable> variableSet)

        {

            YP.addUniqueVariables(_arg1, variableSet);

        }



        public object makeCopy(Variable.CopyStore copyStore)

        {

            return new Functor1(_name, YP.makeCopy(_arg1, copyStore));

        }

    }

}