System.Xml.Xsl.IlGen.OptimizerPatterns.Read C# (CSharp) Method

        public static OptimizerPatterns Read(QilNode nd) {
            XmlILAnnotation ann = nd.Annotation as XmlILAnnotation;
            OptimizerPatterns optPatt = (ann != null) ? ann.Patterns : null;

            if (optPatt == null) {
                if (!nd.XmlType.MaybeMany) {
                    // Expressions with ZeroOrOne cardinality should always report IsDocOrderDistinct and NoContainedNodes
                    if (ZeroOrOneDefault == null) {
                        optPatt = new OptimizerPatterns();
                        optPatt.AddPattern(OptimizerPatternName.IsDocOrderDistinct);
                        optPatt.AddPattern(OptimizerPatternName.SameDepth);
                        optPatt.isReadOnly = true;

                        ZeroOrOneDefault = optPatt;
                    }
                    else {
                        optPatt = ZeroOrOneDefault;
                    }
                }
                else if (nd.XmlType.IsDod) {
                    if (DodDefault == null) {
                        optPatt = new OptimizerPatterns();
                        optPatt.AddPattern(OptimizerPatternName.IsDocOrderDistinct);
                        optPatt.isReadOnly = true;

                        DodDefault = optPatt;
                    }
                    else {
                        optPatt = DodDefault;
                    }
                }
                else {
                    if (MaybeManyDefault == null) {
                        optPatt = new OptimizerPatterns();
                        optPatt.isReadOnly = true;

                        MaybeManyDefault = optPatt;
                    }
                    else {
                        optPatt = MaybeManyDefault;
                    }
                }
            }

            return optPatt;
        }

        /// <summary>
        /// Create and initialize OptimizerPatterns annotation for the specified node.
        /// </summary>
        public static void Inherit(QilNode ndSrc, QilNode ndDst, OptimizerPatternName pattern)
        {
            OptimizerPatterns annSrc = OptimizerPatterns.Read(ndSrc);

            if (annSrc.MatchesPattern(pattern))
            {
                OptimizerPatterns annDst = OptimizerPatterns.Write(ndDst);
                annDst.AddPattern(pattern);

                // Inherit pattern arguments
                switch (pattern)
                {
                case OptimizerPatternName.Step:
                    annDst.AddArgument(OptimizerPatternArgument.StepNode, annSrc.GetArgument(OptimizerPatternArgument.StepNode));
                    annDst.AddArgument(OptimizerPatternArgument.StepInput, annSrc.GetArgument(OptimizerPatternArgument.StepInput));
                    break;

                case OptimizerPatternName.FilterElements:
                    annDst.AddArgument(OptimizerPatternArgument.ElementQName, annSrc.GetArgument(OptimizerPatternArgument.ElementQName));
                    break;

                case OptimizerPatternName.FilterContentKind:
                    annDst.AddArgument(OptimizerPatternArgument.KindTestType, annSrc.GetArgument(OptimizerPatternArgument.KindTestType));
                    break;

                case OptimizerPatternName.EqualityIndex:
                    annDst.AddArgument(OptimizerPatternArgument.IndexedNodes, annSrc.GetArgument(OptimizerPatternArgument.IndexedNodes));
                    annDst.AddArgument(OptimizerPatternArgument.KeyExpression, annSrc.GetArgument(OptimizerPatternArgument.KeyExpression));
                    break;

                case OptimizerPatternName.DodReverse:
                case OptimizerPatternName.JoinAndDod:
                    annDst.AddArgument(OptimizerPatternArgument.DodStep, annSrc.GetArgument(OptimizerPatternArgument.DodStep));
                    break;

                case OptimizerPatternName.MaxPosition:
                    annDst.AddArgument(OptimizerPatternArgument.MaxPosition, annSrc.GetArgument(OptimizerPatternArgument.MaxPosition));
                    break;

                case OptimizerPatternName.SingleTextRtf:
                    annDst.AddArgument(OptimizerPatternArgument.RtfText, annSrc.GetArgument(OptimizerPatternArgument.RtfText));
                    break;
                }
            }
        }