/// <summary>
        /// Parses a document.
        /// </summary>
        public AXmlDocument Parse(SourceText textSource, CancellationToken cancellationToken = default(CancellationToken))
        {
            if (textSource == null)
            {
                throw new ArgumentNullException("textSource");
            }
            var reader          = new TagReader(this, textSource, true);
            var internalObjects = reader.ReadAllObjects(cancellationToken);
            var heuristic       = new TagMatchingHeuristics(textSource);

            return(new AXmlDocument(null, 0, heuristic.CreateDocument(internalObjects, cancellationToken)));
        }
        /// <summary>
        /// Parses a document incrementally into a flat list of tags.
        /// </summary>
        /// <param name="oldParserState">The parser state from a previous call to ParseIncremental(). Use null for the first call.</param>
        /// <param name="newTextSource">The text source for the new document version.</param>
        /// <param name="newParserState">Out: the new parser state, pass this to the next ParseIncremental() call.</param>
        /// <param name="cancellationToken">Optional: cancellation token.</param>
        /// <returns>Parsed tag soup.</returns>
        public AXmlDocument ParseIncremental(
            IncrementalParserState oldParserState, SourceText newTextSource, out IncrementalParserState newParserState,
            CancellationToken cancellationToken = default(CancellationToken))
        {
            if (newTextSource == null)
            {
                throw new ArgumentNullException("newTextSource");
            }
            var internalObjects = InternalParseIncremental(oldParserState, newTextSource, out newParserState, true, cancellationToken);
            var heuristic       = new TagMatchingHeuristics(newTextSource);

            return(new AXmlDocument(null, 0, heuristic.CreateDocument(internalObjects, cancellationToken)));
        }
		/// <summary>
		/// Parses a document incrementally into a flat list of tags.
		/// </summary>
		/// <param name="oldParserState">The parser state from a previous call to ParseIncremental(). Use null for the first call.</param>
		/// <param name="newTextSource">The text source for the new document version.</param>
		/// <param name="newParserState">Out: the new parser state, pass this to the next ParseIncremental() call.</param>
		/// <param name="cancellationToken">Optional: cancellation token.</param>
		/// <returns>Parsed tag soup.</returns>
		public AXmlDocument ParseIncremental(
            IncrementalParserState oldParserState, SourceText newTextSource, out IncrementalParserState newParserState,
			CancellationToken cancellationToken = default(CancellationToken))
		{
			if (newTextSource == null)
				throw new ArgumentNullException("newTextSource");
			var internalObjects = InternalParseIncremental(oldParserState, newTextSource, out newParserState, true, cancellationToken);
			var heuristic = new TagMatchingHeuristics(newTextSource);
			return new AXmlDocument(null, 0, heuristic.CreateDocument(internalObjects, cancellationToken));
		}
		/// <summary>
		/// Parses a document.
		/// </summary>
        public AXmlDocument Parse(SourceText textSource, CancellationToken cancellationToken = default(CancellationToken))
		{
			if (textSource == null)
				throw new ArgumentNullException("textSource");
			var reader = new TagReader(this, textSource, true);
			var internalObjects = reader.ReadAllObjects(cancellationToken);
			var heuristic = new TagMatchingHeuristics(textSource);
			return new AXmlDocument(null, 0, heuristic.CreateDocument(internalObjects, cancellationToken));
		}