(***********************************************************************)
(*                                                                     *)
(*                               TAToo                                 *)
(*                                                                     *)
(*                     Kim Nguyen, LRI UMR8623                         *)
(*                   Université Paris-Sud & CNRS                       *)
(*                                                                     *)
(*  Copyright 2010-2012 Université Paris-Sud and Centre National de la *)
(*  Recherche Scientifique. All rights reserved.  This file is         *)
(*  distributed under the terms of the GNU Lesser General Public       *)
(*  License, with the special exception on linking described in file   *)
(*  ../LICENSE.                                                        *)
(*                                                                     *)
(***********************************************************************)


(** Abstract syntax tree of XPath queries *)

module Ast :
sig
  type path = Absolute of step list | AbsoluteDoS of step list
              | Relative of step list

  and step = axis * test * predicate
  and axis = Self | Attribute | Child | Descendant | DescendantOrSelf
             | FollowingSibling
             | Parent | Ancestor | AncestorOrSelf |PrecedingSibling
             | Preceding | Following
  and test =  Simple of QNameSet.t
  and predicate = Or of predicate*predicate
                  | And of predicate*predicate
                  | Not of predicate
                  | Expr of expression
  and expression =  Path of path
                    | Function of string*expression list
                    | Int of int
                    | String of string
                    | True | False
  type t = path
  val print : Format.formatter -> 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_predicate : Format.formatter -> predicate -> unit
  val print_expression : Format.formatter -> expression -> unit
end


val parse : string -> Ast.path