System.Xml.Schema.SymbolsDictionary.GetParticle C# (CSharp) Method

        public object GetParticle(int symbol) {
            return symbol == last ? particleLast : particles[symbol];
        }

        public override void ExpandTree(InteriorNode parent, SymbolsDictionary symbols, Positions positions)
        {
            SyntaxTreeNode node = null;

            foreach (int num in this.GetResolvedSymbols(symbols))
            {
                if (symbols.GetParticle(num) != this.particle)
                {
                    symbols.IsUpaEnforced = false;
                }
                LeafNode node2 = new LeafNode(positions.Add(num, this.particle));
                if (node == null)
                {
                    node = node2;
                }
                else
                {
                    InteriorNode node3 = new ChoiceNode {
                        LeftChild  = node,
                        RightChild = node2
                    };
                    node = node3;
                }
            }
            if (parent.LeftChild == this)
            {
                parent.LeftChild = node;
            }
            else
            {
                parent.RightChild = node;
            }
        }