Compilation works for all XPath queries from the core specified in the thesis

[tatoo.git] / src / compil.ml

diff --git a/src/compil.ml b/src/compil.ml
index b722656..99e87b5 100644 (file)
--- a/src/compil.ml
+++ b/src/compil.ml
@@ -25,7 +25,7 @@ let trans query =
   let asta = Asta.empty in
   (* Buidling of the ASTA step by step with a special case for the last
      step. Then add a top most state. Each function modifies asta. *)
-  let rec trans = function
+  let rec trans = function             (* builds asta from the bottom of the query *)
     | [s] -> trans_last s
     | s :: tl ->  trans tl; trans_step s
     | [] -> ()
@@ -39,7 +39,7 @@ let trans query =
     Asta.add_quer asta top_st;
     Asta.init_top asta;
     Asta.add_top asta top_st;
-    Asta.add_tr asta (top_st, Asta.any_label, or_top)
+    Asta.add_tr asta (top_st, Asta.any_label, or_top) true
       
   and trans_last (ax,test,pred) =      (* a selecting state is needed *)
     let fo_p = trans_pr pred in
@@ -54,10 +54,10 @@ let trans query =
     let Simple lab = test in
     let tr_selec = (q', lab, fo_p)
     and tr_q = (q, Asta.any_label, form_propa_selec q q' ax) in
-    Asta.add_tr asta tr_selec;
-    Asta.add_tr asta tr_q
+    Asta.add_tr asta tr_selec true;
+    Asta.add_tr asta tr_q true
     
-  and trans_step (ax,test,pred) =
+  and trans_step (ax,test,pred) =      (* add a new state for the step *)
     let fo_p = trans_pr pred
     and q = Asta.new_state() in
     let Simple label = test
@@ -69,8 +69,8 @@ let trans query =
     Asta.add_quer asta q;
     Asta.add_top asta q;
     Asta.add_bot asta q;
-    Asta.add_tr asta tr_next;
-    Asta.add_tr asta tr_propa;
+    Asta.add_tr asta tr_next true;
+    Asta.add_tr asta tr_propa true;
     Asta.init_top asta;
     Asta.add_top asta q
       
@@ -80,22 +80,55 @@ let trans query =
     | Expr False -> Formula.false_
     | Or (p_1,p_2) -> trans_pr(p_1) +| trans_pr(p_2)
     | And (p_1,p_2) -> trans_pr(p_1) *& trans_pr(p_2)
-    | Not (Expr Path q) -> Formula.true_ (* todo *)
-    | Expr Path q -> Formula.true_        (* todo *)
+    | Not (Expr Path q) -> (trans_pr_path false q)
+    | Expr Path q -> (trans_pr_path true q)
     | x -> print_predicate pr_er x; raise Not_core_XPath
       
-  and form_propa q = function
+  and trans_pr_path posi = function            (* builds asta for predicate and gives
+                                                  the formula which must be satsified *)
+    | Relative [] -> if posi then Formula.true_ else Formula.false_
+    | Relative steps -> List.fold_left
+      (fun acc x -> if posi then (`Left *+ x) +| acc else (`Left *- x) +| acc)
+      Formula.false_ (trans_pr_step_l steps)
+    | AbsoluteDoS steps as x -> print pr_er x; raise Not_core_XPath
+    | Absolute steps as x -> print pr_er x; raise Not_core_XPath
+      
+  and trans_pr_step_l = function       (* builds asta for a predicate query *)
+    | [step] -> trans_pr_step [] step
+    | step :: tl -> let list_top = trans_pr_step_l tl in
+                   trans_pr_step list_top step
+    | [] -> failwith "Can not happened! 1"
+
+  and trans_pr_step list (ax,test,pred) = (* add a step on the top of
+                                            list in a predicate *)
+    let form_next =
+      if list = []
+      then trans_pr pred
+      else (trans_pr pred) *&
+       (List.fold_left (fun acc x -> (`Left *+ x) +| acc)
+          Formula.false_ list)
+    and q = Asta.new_state() 
+    and Simple label = test in
+    let tr_next = (q,label, form_next)
+    and tr_propa = (q, Asta.any_label, form_propa q ax) in
+    Asta.add_reco asta q;
+    Asta.add_tr asta tr_next false;
+    Asta.add_tr asta tr_propa false;
+    [q]                                        (* always one element here, but not with self
+                                          axis*)
+
+  and form_propa q = function          (* gives the propagation formula *)
     | Child -> `Right *+ q
     | Descendant -> (`Left *+ q +| `Right *+ q)
     | x -> print_axis pr_er x; raise Not_core_XPath 
 
-  and form_propa_selec q q' = function
+  and form_propa_selec q q' = function (* the same with a  selecting state *)
     | Child -> `Right *+ q +| `Right *+ q'
     | Descendant -> (`Left *+ q +| `Right *+ q) +| (`Left *+ q' +| `Right *+ q')
     | x -> print_axis pr_er x; raise Not_core_XPath 
       
   in
-  match query with
+  match query with                     (* match the top-level query *)
     | Absolute steps -> trans steps; trans_init(); asta
     | AbsoluteDoS steps as x -> print pr_er x; raise Not_core_XPath
     | Relative steps as x -> print pr_er x; raise Not_core_XPath