示例#1
0
        public static WamCompoundTerm Create(CodeCompoundTerm codeCompoundTerm)
        {
            var functor = Functor.Create(codeCompoundTerm.Functor);
            var result  = WamCompoundTerm.Create(functor);

            for (var index = 0; index < functor.Arity; ++index)
            {
                result.Children[index] = WamReferenceTarget.Create(codeCompoundTerm.Children[index]);
            }
            return(result);
        }
示例#2
0
        public static bool FindAll(WamMachine machine, WamReferenceTarget[] arguments)
        {
            Debug.Assert(arguments.Length == 3);

            WamReferenceTarget arg0 = arguments[0].Dereference();
            WamReferenceTarget arg1 = arguments[1].Dereference();
            WamReferenceTarget arg2 = arguments[2].Dereference();

            WamVariable variable = arg0 as WamVariable;

            if (variable == null)
            {
                return(false);
            }

            WamCompoundTerm goal = arg1 as WamCompoundTerm;

            if (goal == null)
            {
                return(false);
            }

            WamVariable result = arg2 as WamVariable;

            if (result == null)
            {
                return(false);
            }

            WamInstructionStreamBuilder builder = new WamInstructionStreamBuilder();

            builder.Write(new WamInstruction(WamInstructionOpCodes.Allocate));
            for (int idx = 0; idx < goal.Functor.Arity; ++idx)
            {
                builder.Write(new WamInstruction(
                                  WamInstructionOpCodes.PutValue,
                                  goal.Children[idx],
                                  new WamInstructionRegister(WamInstructionRegisterTypes.Argument, (byte)idx)));
            }
            builder.Write(new WamInstruction(WamInstructionOpCodes.Call, goal.Functor));
            builder.Write(new WamInstruction(WamInstructionOpCodes.Success));

            machine.PushContext(builder.ToInstructionStream());

            List <WamReferenceTarget> values = new List <WamReferenceTarget>();

            try
            {
                ExecutionResults results = machine.RunToSuccess();
                while (results == ExecutionResults.Success)
                {
                    WamReferenceTarget value = variable.Clone();
                    values.Add(value);

                    results = machine.RunToSuccess();
                }
            }
            finally
            {
                machine.PopContext(true);
            }

            // Unbind the variable from the last results found by the goal.
            //
            variable.Unbind();

            // Unify the output variable with the list of values.
            //
            return(machine.Unify(result, WamReferenceTarget.Create(values)));
        }