Symbol of string option * string * (subst option) * string option
(* h:xref, name, subst, definitionURL *)
| LocalVar of string option * string (* h:xref, name *)
Symbol of string option * string * (subst option) * string option
(* h:xref, name, subst, definitionURL *)
| LocalVar of string option * string (* h:xref, name *)