ChoiceNode.cs

Go to the documentation of this file.

namespace System.Xml.Schema;
 
internal sealed class ChoiceNode : InteriorNode
{
    public override bool IsNullable
    {
        get
        {
            ChoiceNode choiceNode = this;
            SyntaxTreeNode leftChild;
            do
            {
                if (choiceNode.RightChild.IsNullable)
                {
                    return true;
                }
                leftChild = choiceNode.LeftChild;
                choiceNode = leftChild as ChoiceNode;
            }
            while (choiceNode != null);
            return leftChild.IsNullable;
        }
    }
 
    private static void ConstructChildPos(SyntaxTreeNode child, BitSet firstpos, BitSet lastpos, BitSet[] followpos)
    {
        BitSet bitSet = new BitSet(firstpos.Count);
        BitSet bitSet2 = new BitSet(lastpos.Count);
        child.ConstructPos(bitSet, bitSet2, followpos);
        firstpos.Or(bitSet);
        lastpos.Or(bitSet2);
    }
 
    public override void ConstructPos(BitSet firstpos, BitSet lastpos, BitSet[] followpos)
    {
        BitSet bitSet = new BitSet(firstpos.Count);
        BitSet bitSet2 = new BitSet(lastpos.Count);
        ChoiceNode choiceNode = this;
        SyntaxTreeNode leftChild;
        do
        {
            ConstructChildPos(choiceNode.RightChild, bitSet, bitSet2, followpos);
            leftChild = choiceNode.LeftChild;
            choiceNode = leftChild as ChoiceNode;
        }
        while (choiceNode != null);
        leftChild.ConstructPos(firstpos, lastpos, followpos);
        firstpos.Or(bitSet);
        lastpos.Or(bitSet2);
    }
 
    public override void ExpandTree(InteriorNode parent, SymbolsDictionary symbols, Positions positions)
    {
        ExpandTreeNoRecursive(parent, symbols, positions);
    }
}