MarkupBlock - [0..9)::9 - [@:foo bar]
    MarkupTransition - [0..1)::1 - Gen<None> - SpanEditHandler;Accepts:None
        Transition;[@];
    RazorMetaCode - [1..2)::1 - Gen<None> - SpanEditHandler;Accepts:Any
        Colon;[:];
    MarkupTextLiteral - [2..9)::7 - [foo bar] - Gen<Markup> - SpanEditHandler;Accepts:Any
        Text;[foo];
        Whitespace;[ ];
        Text;[bar];
