MarkupBlock - [0..18)::18 - [<foo><bar /></foo>]
    MarkupTagBlock - [0..5)::5 - [<foo>]
        MarkupTextLiteral - [0..5)::5 - [<foo>] - Gen<Markup> - SpanEditHandler;Accepts:None
            OpenAngle;[<];
            Text;[foo];
            CloseAngle;[>];
    MarkupTagBlock - [5..12)::7 - [<bar />]
        MarkupTextLiteral - [5..12)::7 - [<bar />] - Gen<Markup> - SpanEditHandler;Accepts:None
            OpenAngle;[<];
            Text;[bar];
            Whitespace;[ ];
            ForwardSlash;[/];
            CloseAngle;[>];
    MarkupTagBlock - [12..18)::6 - [</foo>]
        MarkupTextLiteral - [12..18)::6 - [</foo>] - Gen<Markup> - SpanEditHandler;Accepts:None
            OpenAngle;[<];
            ForwardSlash;[/];
            Text;[foo];
            CloseAngle;[>];
