Пример #1
0
        /// <summary>
        /// Parse the productions:
        /// implicit_document    ::= block_node DOCUMENT-END*
        ///                          *
        /// explicit_document    ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
        ///                          *************************
        /// </summary>
        private ParsingEvent ParseDocumentStart(bool isImplicit)
        {
            // Parse extra document end indicators.

            if (!isImplicit)
            {
                while (GetCurrentToken() is DocumentEnd)
                {
                    Skip();
                }
            }

            // Parse an isImplicit document.

            if (isImplicit && !(GetCurrentToken() is VersionDirective || GetCurrentToken() is TagDirective || GetCurrentToken() is DocumentStart || GetCurrentToken() is StreamEnd))
            {
                TagDirectiveCollection directives = new TagDirectiveCollection();
                ProcessDirectives(directives);

                states.Push(ParserState.DocumentEnd);

                state = ParserState.BlockNode;

                return(new Events.DocumentStart(null, directives, true, GetCurrentToken().Start, GetCurrentToken().End));
            }

            // Parse an explicit document.

            else if (!(GetCurrentToken() is StreamEnd))
            {
                Mark start = GetCurrentToken().Start;
                TagDirectiveCollection directives       = new TagDirectiveCollection();
                VersionDirective       versionDirective = ProcessDirectives(directives);

                var current = GetCurrentToken();
                if (!(current is DocumentStart))
                {
                    throw new SemanticErrorException(current.Start, current.End, "Did not find expected <document start>.");
                }

                states.Push(ParserState.DocumentEnd);

                state = ParserState.DocumentContent;

                ParsingEvent evt = new Events.DocumentStart(versionDirective, directives, false, start, current.End);
                Skip();
                return(evt);
            }

            // Parse the stream end.

            else
            {
                state = ParserState.StreamEnd;

                ParsingEvent evt = new Events.StreamEnd(GetCurrentToken().Start, GetCurrentToken().End);
                // Do not call skip here because that would throw an exception
                if (scanner.MoveNextWithoutConsuming())
                {
                    throw new InvalidOperationException("The scanner should contain no more tokens.");
                }
                return(evt);
            }
        }
Пример #2
0
 void IParsingEventVisitor.Visit(DocumentStart e)
 {
     throw new NotSupportedException();
 }