(* Copyright (C) 2000, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * HELM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://cs.unibo.it/helm/.
 *)

(*
 * implementazione del comando PATTERN
 *)

open Dbconn;;
open Utility;;
open Eval;;
open Mathql_semantics;;

let pattern_ex (apreamble, apattern, afragid) =
 let c = pgc () in
  (*let r1 = helm_class_id "MathResource" in*)
   (*let qq = "select att0 from t" ^ r1 ^ " where att0 " ^ (pattern_match apreamble apattern afragid) ^ " order by t" ^ r1 ^ ".att0 asc" in*)
   let qq = "select uri from registry where uri " ^ (pattern_match (apreamble, apattern, afragid)) ^ " order by registry.uri asc" in
   (*let _ = print_endline qq in*)
    let res =
     c#exec (qq)
    in
     List.map
      (function uri -> {uri = uri ; attributes = []})
      (pgresult_to_string_list res)
;;