X-Git-Url: http://git.nguyen.vg/gitweb/?a=blobdiff_plain;f=finiteCofinite.ml;fp=finiteCofinite.ml;h=32f0e4887a16f45370303f2d34267bf052933b7e;hb=d04661689691b4587cfc45a35e98604fcdc2b878;hp=0000000000000000000000000000000000000000;hpb=f84dd2f6de7d5da16da729dc2e91cbdeb3585d75;p=SXSI%2Fxpathcomp.git

diff --git a/finiteCofinite.ml b/finiteCofinite.ml
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+(******************************************************************************)
+(*  SXSI : XPath evaluator                                                    *)
+(*  Kim Nguyen (Kim.Nguyen@nicta.com.au)                                      *)
+(*  Copyright NICTA 2008                                                      *)
+(*  Distributed under the terms of the LGPL (see LICENCE)                     *)
+(******************************************************************************)
+
+exception InfiniteSet
+module type S = 
+sig
+  type elt
+  type t
+  val empty : t
+  val any : t
+  val is_empty : t -> bool
+  val is_any : t -> bool
+  val is_finite : t -> bool
+  val kind : t -> [ `Finite | `Cofinite ]
+  val singleton : elt -> t
+  val mem : elt -> t -> bool
+  val add : elt -> t -> t
+  val remove : elt -> t -> t
+  val cup : t -> t -> t
+  val cap : t -> t -> t
+  val diff : t -> t -> t
+  val neg : t -> t
+  val compare : t -> t -> int
+  val subset : t -> t -> bool
+  val kind_split : t list -> t * t
+  val fold : (elt -> 'a -> 'a) -> t -> 'a -> 'a
+  val for_all : (elt -> bool) -> t -> bool
+  val exists : (elt -> bool) -> t -> bool
+  val filter : (elt -> bool) -> t -> t
+  val partition : (elt -> bool) -> t -> t * t
+  val cardinal : t -> int
+  val elements : t -> elt list
+  val from_list : elt list -> t
+  val choose : t -> elt
+  val hash : t -> int
+  val equal : t -> t -> bool
+end
+
+module Make (E : Sigs.Set) : S with type elt = E.elt =
+struct
+
+  type elt = E.elt
+  type t = Finite of E.t | CoFinite of E.t
+
+
+  let empty = Finite E.empty
+  let any = CoFinite E.empty
+
+  let is_empty =  function
+      Finite s when E.is_empty s -> true
+    | _ -> false
+
+  let is_any = function
+      CoFinite s when E.is_empty s -> true
+    | _ -> false
+
+  let is_finite = function
+    | Finite _ -> true | _ -> false
+
+  let kind = function
+      Finite _ -> `Finite 
+    | _ -> `Cofinite 
+
+  let mem x = function Finite s -> E.mem x s
+    | CoFinite s -> not (E.mem x s)
+
+  let singleton x = Finite (E.singleton x)
+  let add e = function 
+    | Finite s -> Finite (E.add e s)
+    | CoFinite s -> CoFinite (E.remove e s)
+  let remove e = function
+    | Finite s -> Finite (E.remove e s)
+    | CoFinite s -> CoFinite (E.add e s)
+	
+  let cup s t = match (s,t) with
+    | Finite s, Finite t -> Finite (E.union s t)
+    | CoFinite s, CoFinite t -> CoFinite ( E.inter s t)
+    | Finite s, CoFinite t -> CoFinite (E.diff t s)
+    | CoFinite s, Finite t-> CoFinite (E.diff s t)
+
+  let cap s t = match (s,t) with
+    | Finite s, Finite t -> Finite (E.inter s t)
+    | CoFinite s, CoFinite t -> CoFinite (E.union s t)
+    | Finite s, CoFinite t -> Finite (E.diff s t)
+    | CoFinite s, Finite t-> Finite (E.diff t s)
+	
+  let diff s t = match (s,t) with
+    | Finite s, Finite t -> Finite (E.diff s t)
+    | Finite s, CoFinite t -> Finite(E.inter s t)
+    | CoFinite s, Finite t -> CoFinite(E.union t s)
+    | CoFinite s, CoFinite t -> Finite (E.diff t s)
+
+  let neg = function 
+    | Finite s -> CoFinite s
+    | CoFinite s -> Finite s
+	
+  let compare s t = match (s,t) with
+    | Finite s , Finite t -> E.compare s t
+    | CoFinite s , CoFinite t -> E.compare t s
+    | Finite _, CoFinite _ -> -1
+    | CoFinite _, Finite _ -> 1
+	
+  let subset s t = match (s,t) with
+    | Finite s , Finite t -> E.subset s t
+    | CoFinite s , CoFinite t -> E.subset t s
+    | Finite s, CoFinite t -> E.is_empty (E.inter s t)
+    | CoFinite _, Finite _ -> false
+
+	(* given a  list l of type t list, 
+	   returns two sets (f,c) where :
+	   - f is the union of all the finite sets of l
+	   - c is the union of all the cofinite sets of l
+	   - f and c are disjoint
+	   Invariant : cup f c = List.fold_left cup empty l
+
+	   We treat the CoFinite part explicitely :
+	*)
+
+  let kind_split l =
+    
+    let rec next_finite_cofinite facc cacc = function 
+      | [] -> Finite facc, CoFinite (E.diff cacc facc)
+      | Finite s ::r -> next_finite_cofinite (E.union s facc) cacc r
+      | CoFinite _ ::r when E.is_empty cacc -> next_finite_cofinite facc cacc r
+      | CoFinite s ::r -> next_finite_cofinite facc (E.inter cacc s) r
+    in
+    let rec first_cofinite facc = function
+      | [] -> empty,empty
+      | Finite s :: r-> first_cofinite (E.union s facc) r
+      | CoFinite s :: r -> next_finite_cofinite facc s r  
+    in
+      first_cofinite E.empty l
+	
+  let fold f t a = match t with
+    | Finite s -> E.fold f s a
+    | CoFinite _ -> raise InfiniteSet
+
+  let for_all f = function
+    | Finite s -> E.for_all f s
+    | CoFinite _ -> raise InfiniteSet
+
+  let exists f = function
+    | Finite s -> E.exists f s
+    | CoFinite _ -> raise InfiniteSet
+
+  let filter f = function
+    | Finite s -> Finite (E.filter f s)
+    | CoFinite _ -> raise InfiniteSet
+
+  let partition f = function
+    | Finite s -> let a,b = E.partition f s in Finite a,Finite b
+    | CoFinite _ -> raise InfiniteSet
+
+  let cardinal = function
+    | Finite s -> E.cardinal s
+    | CoFinite _ -> raise InfiniteSet
+
+  let elements = function
+    | Finite s -> E.elements s
+    | CoFinite _ -> raise InfiniteSet
+	
+  let from_list l = 
+    Finite(List.fold_left (fun x a -> E.add a x ) E.empty l)
+
+  let choose = function
+      Finite s -> E.choose s
+    | _ -> raise InfiniteSet
+
+  let equal a b = 
+    match a,b with
+      | Finite x, Finite y | CoFinite x, CoFinite y -> E.equal x y
+      | _ -> false
+
+  let hash = 
+    function Finite x -> (E.hash x)
+      | CoFinite x -> ( ~-(E.hash x) land max_int)
+
+end
+