/// <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);
}
}
void IParsingEventVisitor.Visit(DocumentStart e)
{
throw new NotSupportedException();
}
