optimiser la fonction eval_query_tree par l'ajoutation d'un hashtbl 'table_query_tree'

[tatoo.git] / src / query_tree.ml

diff --git a/src/query_tree.ml b/src/query_tree.ml
index 79aee48..018036b 100644 (file)
--- a/src/query_tree.ml
+++ b/src/query_tree.ml
@@ -125,25 +125,35 @@ let debug tree q l =
     Format.pp_print_flush Format.std_formatter ();
   end
 
+let table_query_tree = Hashtbl.create 97 
 
+  
 let rec eval_query_tree tree start q =
   let resultat = 
-    match q with
-      | Start ->  start
-      | Dom -> all_nodes tree
-      | Tag t -> element_by_tag tree t
-      | Axis (a,q1) -> let ls = eval_query_tree tree start q1 in
-                      eval_axis tree ls a
-      | Binop (op,q1,q2)-> begin
-       let ls1 = eval_query_tree tree start q1 in
-       let ls2 = eval_query_tree tree start q2 in
-       match op with     
-         | Union -> union_list tree ls1 ls2        
-         | Inter -> inter_list tree ls1 ls2
-         | Diff -> diff_list tree ls1 ls2
-      end
+    begin
+      try
+       Hashtbl.find table_query_tree q
+      with Not_found ->        
+       let res =
+       match q with
+         | Start -> start
+         | Dom ->  all_nodes tree          
+         | Tag t -> element_by_tag tree t                   
+         | Axis (a,q1) -> let ls = eval_query_tree tree start q1 in
+                          eval_axis tree ls a                     
+         | Binop (op,q1,q2)-> begin
+           let ls1 = eval_query_tree tree start q1 in
+           let ls2 = eval_query_tree tree start q2 in
+           match op with         
+             | Union -> union_list tree ls1 ls2            
+             | Inter -> inter_list tree ls1 ls2
+             | Diff -> diff_list tree ls1 ls2
+         end
+       in
+       Hashtbl.add table_query_tree q res;
+       compteur := !compteur + (List.length res);
+       res
+    end
   in
   debug tree q resultat;
-  compteur := !compteur + (List.length resultat);
   resultat
-