doc:[html null null]
tag:html:1<
tag:head:2<
tag:title:3<
txt:[Hello]
tag:title:3>
tag:head:2>
tag:body:2<
com:[comment]
tag:p:3<
com:[]
txt:[Paragraph]
tag:br:4<>
txt:[new line]
tag:p:3>
tag:body:2>
tag:html:1>