Markup block - Gen<None> - 10 - (0:0,0)
    Markup span - Gen<Markup> - [] - SpanEditHandler;Accepts:Any - (0:0,0) - Tokens:1
        SyntaxKind.Unknown;[];
    Directive block - Gen<Directive:{namespace;SingleLine;Unrestricted}> - 10 - (0:0,0)
        Transition span - Gen<None> - [@] - SpanEditHandler;Accepts:None - (0:0,0) - Tokens:1
            SyntaxKind.Transition;[@];
        MetaCode span - Gen<None> - [namespace] - SpanEditHandler;Accepts:None - (1:0,1) - Tokens:1
            SyntaxKind.Keyword;[namespace];
    Markup span - Gen<Markup> - [] - SpanEditHandler;Accepts:Any - (10:0,10) - Tokens:1
        SyntaxKind.Unknown;[];
