/* * Copyright (C) 2007-2008, Jeff Thompson * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of the copyright holder nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ using System; using System.Collections.Generic; namespace OpenSim.Region.ScriptEngine.Shared.YieldProlog { public class Functor3 : IUnifiable { public readonly Atom _name; public readonly object _arg1; public readonly object _arg2; public readonly object _arg3; public Functor3(Atom name, object arg1, object arg2, object arg3) { _name = name; _arg1 = arg1; _arg2 = arg2; _arg3 = arg3; } public Functor3(string name, object arg1, object arg2, object arg3) : this(Atom.a(name), arg1, arg2, arg3) { } // disable warning on l1, don't see how we can // code this differently #pragma warning disable 0168, 0219 /// If arg is another Functor3, then succeed (yield once) if this and arg have the /// same name and all 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). public IEnumerable<bool> unify(object arg) { arg = YP.getValue(arg); if (arg is Functor3) { Functor3 argFunctor = (Functor3)arg; if (_name.Equals(argFunctor._name)) { foreach (bool l1 in YP.unify(_arg1, argFunctor._arg1)) { foreach (bool l2 in YP.unify(_arg2, argFunctor._arg2)) { foreach (bool l3 in YP.unify(_arg3, argFunctor._arg3)) 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) + ", " + YP.getValue(_arg2) + ", " + YP.getValue(_arg3) + ")"; } public bool termEqual(object term) { term = YP.getValue(term); if (term is Functor3) { Functor3 termFunctor = (Functor3)term; return _name.Equals(termFunctor._name) && YP.termEqual(_arg1, termFunctor._arg1) && YP.termEqual(_arg2, termFunctor._arg2) && YP.termEqual(_arg3, termFunctor._arg3); } return false; } public bool lessThan(Functor3 functor) { // Do the equal check first since it is faster. if (!_name.Equals(functor._name)) return _name.lessThan(functor._name); if (!YP.termEqual(_arg1, functor._arg1)) return YP.termLessThan(_arg1, functor._arg1); if (!YP.termEqual(_arg2, functor._arg2)) return YP.termLessThan(_arg2, functor._arg2); return YP.termLessThan(_arg3, functor._arg3); } public bool ground() { return YP.ground(_arg1) && YP.ground(_arg2) && YP.ground(_arg3); } public void addUniqueVariables(List<Variable> variableSet) { YP.addUniqueVariables(_arg1, variableSet); YP.addUniqueVariables(_arg2, variableSet); YP.addUniqueVariables(_arg3, variableSet); } public object makeCopy(Variable.CopyStore copyStore) { return new Functor3(_name, YP.makeCopy(_arg1, copyStore), YP.makeCopy(_arg2, copyStore), YP.makeCopy(_arg3, copyStore)); } } }