Dom -> Format.fprintf fmt "Dom"
| Start -> Format.fprintf fmt "Start"
| Tag (t,k) -> Format.fprintf fmt "Tag(%a, %a)" QNameSet.print t Tree.NodeKind.print k
Dom -> Format.fprintf fmt "Dom"
| Start -> Format.fprintf fmt "Start"
| Tag (t,k) -> Format.fprintf fmt "Tag(%a, %a)" QNameSet.print t Tree.NodeKind.print k