+ val text : QNameSet.t
+ val node : QNameSet.t
+ val star : QNameSet.t
+ val print_binop : Format.formatter -> binop -> unit
+ val print_unop : Format.formatter -> unop -> unit
+ val print_path : Format.formatter -> path -> unit
+ val print_single_path : Format.formatter -> single_path -> unit
+ val print_step : Format.formatter -> step -> unit
+ val print_axis : Format.formatter -> axis -> unit
+ val print_test : Format.formatter -> test -> unit
+ val print_expr : Format.formatter -> expr -> unit
+ end