discriminations nets

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@123 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 75 insertions, 0 deletions

diff --git a/tactics/nbtermdn.ml b/tactics/nbtermdn.ml
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+
+(* $Id$ *)
+
+open Util
+open Names
+open Generic
+open Term
+open Libobject
+open Library
+
+(* Named, bounded-depth, term-discrimination nets.
+   Implementation:
+   Term-patterns are stored in discrimination-nets, which are
+   themselves stored in a hash-table, indexed by the first label.
+   They are also stored by name in a table on-the-side, so that we can
+   override them if needed. *)
+
+(* The former comments are from Chet.
+   See the module dn.ml for further explanations.
+   Eduardo (5/8/97) *)
+
+type ('na,'a) t = {
+  mutable table : ('na,constr * 'a) Gmap.t;
+  mutable patterns : (Termdn.lbl option,'a Btermdn.t) Gmap.t }
+
+type ('na,'a) frozen_t = 
+    ('na,constr * 'a) Gmap.t * (Termdn.lbl option,'a Btermdn.t) Gmap.t
+
+let create () =
+  { table = Gmap.empty;
+    patterns = Gmap.empty }
+
+let get_dn dnm hkey =
+  try Gmap.find hkey dnm with Not_found -> Btermdn.create ()
+
+let add dn (na,(pat,valu)) =
+  let hkey = option_app fst (Termdn.constr_pat_discr pat) in 
+  dn.table <- Gmap.add na (pat,valu) dn.table;
+  let dnm = dn.patterns in
+  dn.patterns <- Gmap.add hkey (Btermdn.add (get_dn dnm hkey) (pat,valu)) dnm
+    
+let rmv dn na =
+  let (pat,valu) = Gmap.find na dn.table in
+  let hkey = option_app fst (Termdn.constr_pat_discr pat) in 
+  dn.table <- Gmap.remove na dn.table;
+  let dnm = dn.patterns in
+  dn.patterns <- Gmap.add hkey (Btermdn.rmv (get_dn dnm hkey) (pat,valu)) dnm
+
+let in_dn dn na = Gmap.mem na dn.table
+			  
+let remap ndn na (pat,valu) =
+  rmv ndn na;
+  add ndn (na,(pat,valu))
+
+let lookup dn valu =
+  let hkey = option_app fst (Termdn.constr_val_discr valu) in 
+  try Btermdn.lookup (Gmap.find hkey  dn.patterns) valu with Not_found -> []
+
+let app f dn = Gmap.iter f dn.table
+		       
+let dnet_depth = Btermdn.dnet_depth
+		   
+let freeze dn = (dn.table, dn.patterns)
+
+let unfreeze (fnm,fdnm) dn =
+  dn.table <- fnm;
+  dn.patterns <- fdnm
+
+let empty dn = 
+  dn.table <- Gmap.empty;
+  dn.patterns <- Gmap.empty
+
+let to2lists dn = 
+  (Gmap.to_list dn.table, Gmap.to_list dn.patterns)
+