Ppxlib_ast.Location_error
val of_exn : exn -> t option
val register_error_of_exn : (exn -> t option) -> unit
val message : t -> string
val make : loc:Warnings.loc -> string -> sub:(Warnings.loc * string) list -> t
val to_extension : t -> Migrate_parsetree.Ast_412.Parsetree.extension
val raise : t -> 'a
val update_loc : t -> Warnings.loc -> t