types.ml 38.2 KB
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open Recursive
open Printf
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open Ident
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let map_sort f l =
  SortedList.from_list (List.map f l)
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module HashedString = 
struct 
  type t = string 
  let hash = Hashtbl.hash
  let equal = (=)
end
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type const = 
  | Integer of Intervals.v
  | Atom of Atoms.v
  | Char of Chars.v
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type pair_kind = [ `Normal | `XML ]

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type 'a node0 = { id : int; mutable descr : 'a }

module NodePair = struct
  type 'a t = 'a node0 * 'a node0
  let compare (x1,y1) (x2,y2) =
    if x1.id < x2.id then -1
    else if x1.id > x2.id then 1
    else y1.id - y2.id
  let equal (x1,y1) (x2,y2) = (x1==x2) && (y1==y2)
  let hash (x,y) = x.id + 17 * y.id
end 

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module RecArg = struct
  type 'a t = bool * 'a node0 label_map
  
  let rec compare_rec r1 r2 =
    if r1 == r2 then 0
    else match (r1,r2) with
      | (l1,x1)::r1,(l2,x2)::r2 ->
	  if ((l1:int) < l2) then -1 
	  else if (l1 > l2) then 1 
	  else if x1.id < x2.id then -1
	  else if x1.id > x2.id then 1
	  else compare_rec r1 r2
      | ([],_) -> -1
      | _ -> 1

  let compare (o1,r1) (o2,r2) =
    if o1 && not o2 then -1 
    else if o2 && not o1 then 1
    else compare_rec (LabelMap.get r1) (LabelMap.get r2)

  let rec equal_rec r1 r2 =
    (r1 == r2) ||
    match (r1,r2) with
      | (l1,x1)::r1,(l2,x2)::r2 ->
	  (x1.id == x2.id) && (l1 == l2) && (equal_rec r1 r2)
      | _ -> false

  let equal (o1,r1) (o2,r2) =
    (o1 == o2) && (equal_rec (LabelMap.get r1) (LabelMap.get r2))

  let rec hash_rec accu = function
    | (l,x)::rem -> hash_rec (257 * accu + 17 * l + x.id) rem
    | [] -> accu + 5
      
  let hash (o,r) = hash_rec (if o then 2 else 1) (LabelMap.get r)
end

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module BoolPair = Boolean.Make(NodePair)
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module BoolRec = Boolean.Make(RecArg)
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type descr = {
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  atoms : Atoms.t;
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  ints  : Intervals.t;
  chars : Chars.t;
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  times : descr BoolPair.t;
  xml   : descr BoolPair.t;
  arrow : descr BoolPair.t;
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  record: descr BoolRec.t;
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  absent: bool
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} and node = descr node0
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let empty = { 
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  times = BoolPair.empty; 
  xml   = BoolPair.empty; 
  arrow = BoolPair.empty; 
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  record= BoolRec.empty;
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  ints  = Intervals.empty;
  atoms = Atoms.empty;
  chars = Chars.empty;
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  absent= false;
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}
	      
let any =  {
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  times = BoolPair.full; 
  xml   = BoolPair.full; 
  arrow = BoolPair.full; 
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  record= BoolRec.full; 
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  ints  = Intervals.any;
  atoms = Atoms.any;
  chars = Chars.any;
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  absent= false;
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}
	     
	     
let interval i = { empty with ints = i }
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let times x y = { empty with times = BoolPair.atom (x,y) }
let xml x y = { empty with xml = BoolPair.atom (x,y) }
let arrow x y = { empty with arrow = BoolPair.atom (x,y) }
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let record label t = 
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  { empty with record = BoolRec.atom (true,LabelMap.singleton label t) }
let record' (x : bool * node Ident.label_map) =
  { empty with record = BoolRec.atom x }
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let atom a = { empty with atoms = a }
let char c = { empty with chars = c }
let constant = function
  | Integer i -> interval (Intervals.atom i)
  | Atom a -> atom (Atoms.atom a)
  | Char c -> char (Chars.atom c)
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let cup x y = 
  if x == y then x else {
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    times = BoolPair.cup x.times y.times;
    xml   = BoolPair.cup x.xml y.xml;
    arrow = BoolPair.cup x.arrow y.arrow;
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    record= BoolRec.cup x.record y.record;
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    ints  = Intervals.cup x.ints  y.ints;
    atoms = Atoms.cup x.atoms y.atoms;
    chars = Chars.cup x.chars y.chars;
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    absent= x.absent || y.absent;
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  }
    
let cap x y = 
  if x == y then x else {
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    times = BoolPair.cap x.times y.times;
    xml   = BoolPair.cap x.xml y.xml;
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    record= BoolRec.cap x.record y.record;
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    arrow = BoolPair.cap x.arrow y.arrow;
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    ints  = Intervals.cap x.ints  y.ints;
    atoms = Atoms.cap x.atoms y.atoms;
    chars = Chars.cap x.chars y.chars;
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    absent= x.absent && y.absent;
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  }
    
let diff x y = 
  if x == y then empty else {
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    times = BoolPair.diff x.times y.times;
    xml   = BoolPair.diff x.xml y.xml;
    arrow = BoolPair.diff x.arrow y.arrow;
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    record= BoolRec.diff x.record y.record;
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    ints  = Intervals.diff x.ints  y.ints;
    atoms = Atoms.diff x.atoms y.atoms;
    chars = Chars.diff x.chars y.chars;
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    absent= x.absent && not y.absent;
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  }
    
let count = ref 0
let make () = incr count; { id = !count; descr = empty }
let define n d = n.descr <- d
let cons d = incr count; { id = !count; descr = d }
let descr n = n.descr
let internalize n = n
let id n = n.id
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let rec compare_rec r1 r2 =
  if r1 == r2 then 0
  else match (r1,r2) with
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    | (l1,x1)::r1,(l2,x2)::r2 ->
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	if ((l1:int) < l2) then -1 
	else if (l1 > l2) then 1 
	else if x1.id < x2.id then -1
	else if x1.id > x2.id then 1
	else compare_rec r1 r2
    | ([],_) -> -1
    | _ -> 1

let rec compare_rec_list l1 l2  =
  if l1 == l2 then 0 
  else match (l1,l2) with
    | (o1,r1)::l1, (o2,r2)::l2 ->
	if o2 && not o1 then -1
	else if o1 && not o2 then 1
	else let c = compare_rec r1 r2 in if c <> 0 then c 
	else compare_rec_list l1 l2
    | ([],_) -> -1
    | _ -> 1

let rec compare_rec_bool l1 l2  =
  if l1 == l2 then 0 
  else match (l1,l2) with
    | (p1,n1)::l1, (p2,n2)::l2 ->
	let c = compare_rec_list p1 p2 in if c <> 0 then c 
	else let c = compare_rec_list n1 n2 in if c <> 0 then c 
	else compare_rec_bool l1 l2
    | ([],_) -> -1
    | _ -> 1

let rec compare_times_list l1 l2  =
  if l1 == l2 then 0 
  else match (l1,l2) with
    | (x1,y1)::l1, (x2,y2)::l2 ->
	if (x1.id < x2.id) then -1
	else if (x1.id > x2.id) then 1 
	else if (y1.id < y2.id) then -1
	else if (y1.id > y2.id) then 1 
	else compare_times_list l1 l2
    | ([],_) -> -1
    | _ -> 1

let rec compare_times_bool l1 l2  =
  if l1 == l2 then 0 
  else match (l1,l2) with
    | (p1,n1)::l1, (p2,n2)::l2 ->
	let c = compare_times_list p1 p2 in if c <> 0 then c 
	else let c = compare_times_list n1 n2 in if c <> 0 then c 
	else compare_times_bool l1 l2
    | ([],_) -> -1
    | _ -> 1
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let rec equal_rec r1 r2 =
  (r1 == r2) ||
  match (r1,r2) with
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    | (l1,x1)::r1,(l2,x2)::r2 ->
	(x1.id = x2.id) && (l1 == l2) && (equal_rec r1 r2)
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    | _ -> false
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let rec equal_rec_list l1 l2  =
  (l1 == l2) ||
  match (l1,l2) with
    | (o1,r1)::l1, (o2,r2)::l2 ->
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	(o1 == o2) &&
	(equal_rec r1 r2) && (equal_rec_list l1 l2)
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    | _ -> false
	
let rec equal_rec_bool l1 l2 =
  (l1 == l2) ||
  match (l1,l2) with
    | (p1,n1)::l1, (p2,n2)::l2 -> 
	(equal_rec_list p1 p2) &&
	(equal_rec_list n1 n2) &&
        (equal_rec_bool l1 l2)
    | _ -> false
	
let rec equal_times_list l1 l2  =
  (l1 == l2) ||
  match (l1,l2) with
    | (x1,y1)::l1, (x2,y2)::l2 -> 
	(x1.id = x2.id) &&
	(y1.id = y2.id) &&
	(equal_times_list l1 l2)
    | _ -> false
	
let rec equal_times_bool l1 l2 =
  (l1 == l2) ||
  match (l1,l2) with
    | (p1,n1)::l1, (p2,n2)::l2 -> 
	(equal_times_list p1 p2) &&
	(equal_times_list n1 n2) &&
        (equal_times_bool l1 l2)
    | _ -> false
	
let equal_descr a b =
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  (Atoms.equal a.atoms b.atoms) &&
  (Chars.equal a.chars b.chars) &&
  (Intervals.equal a.ints  b.ints) &&
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  (BoolPair.equal a.times b.times) &&
  (BoolPair.equal a.xml b.xml) &&
  (BoolPair.equal a.arrow b.arrow) &&
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  (BoolRec.equal a.record b.record) &&
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  (a.absent == b.absent)
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let compare_descr a b =
  let c = compare a.atoms b.atoms in if c <> 0 then c
  else let c = compare a.chars b.chars in if c <> 0 then c
  else let c = compare a.ints b.ints in if c <> 0 then c
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  else let c = BoolPair.compare a.times b.times in if c <> 0 then c
  else let c = BoolPair.compare a.xml b.xml in if c <> 0 then c
  else let c = BoolPair.compare a.arrow b.arrow in if c <> 0 then c
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  else let c = BoolRec.compare a.record b.record in if c <> 0 then c
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  else if a.absent && not b.absent then -1
  else if b.absent && not a.absent then 1
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  else 0

(*
let compare_descr a b =
  let c = compare_descr a b in
  assert (c = compare a b);
  c
*)


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let rec hash_times_list accu = function
  | (x,y)::l ->
      hash_times_list (accu * 257 + x.id * 17 + y.id) l
  | [] -> accu + 17
      
let rec hash_times_bool accu = function
  | (p,n)::l -> 
      hash_times_bool (hash_times_list (hash_times_list accu p) n) l
  | [] -> accu + 3
      
let rec hash_rec accu = function
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  | (l,x)::rem ->
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      hash_rec (257 * accu + 17 * (LabelPool.hash l) + x.id) rem
  | [] -> accu + 5
      
let rec hash_rec_list accu = function
  | (o,r)::l ->
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      hash_rec_list (hash_rec (if o then accu*3 else accu) r) l
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  | [] -> accu + 17
      
let rec hash_rec_bool accu = function
  | (p,n)::l -> 
      hash_rec_bool (hash_rec_list (hash_rec_list accu p) n) l
  | [] -> accu + 3
      
      
let hash_descr a =
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  let accu = Chars.hash 1 a.chars in
  let accu = Intervals.hash accu a.ints in
  let accu = Atoms.hash accu a.atoms in
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  let accu = 17 * accu + BoolPair.hash a.times in
  let accu = 17 * accu + BoolPair.hash a.xml in
  let accu = 17 * accu + BoolPair.hash a.arrow in
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  let accu = 17 * accu + BoolRec.hash a.record in
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  let accu = if a.absent then accu+5 else accu in
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  accu
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module DescrHash = 
  Hashtbl.Make(
    struct 
      type t = descr
      let hash = hash_descr
      let equal = equal_descr
    end
  )

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let print_descr = ref (fun _ _  -> assert false)

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let neg x = diff any x

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let any_node = cons any

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module LabelS = Set.Make(LabelPool)
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let get_record r =
  let labs accu (_,r) = 
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    List.fold_left 
      (fun accu (l,_) -> LabelS.add l accu) accu (LabelMap.get r) in
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  let extend descrs labs (o,r) =
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    let rec aux i labs r =
      match labs with
	| [] -> ()
	| l1::labs ->
	    match r with
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	      | (l2,x)::r when l1 == l2 -> 
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		  descrs.(i) <- cap descrs.(i) (descr x);
		  aux (i+1) labs r
	      | r ->
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		  if not o then descrs.(i) <- 
		    cap descrs.(i) { empty with absent = true };
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		  aux (i+1) labs r
    in
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    aux 0 labs (LabelMap.get r);
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    o
  in
  let line (p,n) =
    let labels = 
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      List.fold_left labs (List.fold_left labs LabelS.empty p) n in
    let labels = LabelS.elements labels in
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    let nlab = List.length labels in
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    let mk () = Array.create nlab { any with absent = true } in
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    let pos = mk () in
    let opos = List.fold_left 
		 (fun accu x -> 
		    (extend pos labels x) && accu)
		 true p in
    let p = (opos, pos) in

    let n = List.map (fun x ->
			let neg = mk () in
			let o = extend neg labels x in
			(o,neg)
		     ) n in
    (labels,p,n)
  in
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  List.map line (BoolRec.get r)
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module DescrMap = Map.Make(struct type t = descr let compare = compare end)
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let check d =
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  BoolPair.check d.times;
  BoolPair.check d.xml;
  BoolPair.check d.arrow;
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  BoolRec.check d.record;
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  ()

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(* Subtyping algorithm *)

let diff_t d t = diff d (descr t)
let cap_t d t = cap d (descr t)
let cup_t d t = cup d (descr t)
let cap_product l =
  List.fold_left 
    (fun (d1,d2) (t1,t2) -> (cap_t d1 t1, cap_t d2 t2))
    (any,any)
    l

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let rec exists max f =
  (max > 0) && (f (max - 1) || exists (max - 1) f)

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let trivially_empty d = equal_descr d empty
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exception NotEmpty
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type slot = { mutable status : status; 
	       mutable notify : notify;
	       mutable active : bool }
and status = Empty | NEmpty | Maybe
and notify = Nothing | Do of slot * (slot -> unit) * notify

let memo = DescrHash.create 33000

let marks = ref [] 
let slot_empty = { status = Empty; active = false; notify = Nothing }
let slot_not_empty = { status = NEmpty; active = false; notify = Nothing }

let rec notify = function
  | Nothing -> ()
  | Do (n,f,rem) -> 
      if n.status = Maybe then (try f n with NotEmpty -> ());
      notify rem

let rec iter_s s f = function
  | [] -> ()
  | arg::rem -> f arg s; iter_s s f rem


let set s =
  s.status <- NEmpty;
  notify s.notify;
  raise NotEmpty

let rec big_conj f l n =
  match l with
    | [] -> set n
    | [arg] -> f arg n
    | arg::rem ->
	let s = { status = Maybe; active = false; notify = Do (n,(big_conj f rem), Nothing) } in
	try 
	  f arg s;
	  if s.active then n.active <- true
	with NotEmpty -> if n.status = NEmpty then raise NotEmpty

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let rec guard a f n =
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  match slot a with
    | { status = Empty } -> ()
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    | { status = Maybe } as s -> 
	n.active <- true; s.notify <- Do (n,f,s.notify)
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    | { status = NEmpty } -> f n
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and slot d =
  if not ((Intervals.is_empty d.ints) && 
	  (Atoms.is_empty d.atoms) &&
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	  (Chars.is_empty d.chars) &&
	  (not d.absent)) then slot_not_empty 
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  else try DescrHash.find memo d
  with Not_found ->
    let s = { status = Maybe; active = false; notify = Nothing } in
    DescrHash.add memo d s;
    (try
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       iter_s s check_times (BoolPair.get d.times);
       iter_s s check_times (BoolPair.get d.xml);
       iter_s s check_arrow (BoolPair.get d.arrow);
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       iter_s s check_record (get_record d.record);
       if s.active then marks := s :: !marks else s.status <- Empty;
     with
	 NotEmpty -> ());
    s

and check_times (left,right) s =
  let rec aux accu1 accu2 right s = match right with
    | (t1,t2)::right ->
	if trivially_empty (cap_t accu1 t1) || 
	   trivially_empty (cap_t accu2 t2) then
	     aux accu1 accu2 right s
	else
          let accu1' = diff_t accu1 t1 in guard accu1' (aux accu1' accu2 right) s;
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          let accu2' = diff_t accu2 t2 in guard accu2' (aux accu1 accu2' right) s 
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    | [] -> set s
  in
  let (accu1,accu2) = cap_product left in
  guard accu1 (guard accu2 (aux accu1 accu2 right)) s
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and check_arrow (left,right) s =
  let single_right (s1,s2) s =
    let rec aux accu1 accu2 left s = match left with
      | (t1,t2)::left ->
          let accu1' = diff_t accu1 t1 in guard accu1' (aux accu1' accu2 left) s;
          let accu2' = cap_t  accu2 t2 in guard accu2' (aux accu1 accu2' left) s
      | [] -> set s
    in
    let accu1 = descr s1 in
    guard accu1 (aux accu1 (neg (descr s2)) left) s
  in
  big_conj single_right right s
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and check_record (labels,(oleft,left),rights) s =
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  let rec aux rights s = match rights with
    | [] -> set s
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    | (oright,right)::rights ->
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	let next =
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	  (oleft && (not oright)) || (* ggg... why ???  check this line *)
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	  exists (Array.length left)
	    (fun i ->
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	       trivially_empty (cap left.(i) right.(i)))
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	in
	if next then aux rights s
	else
	  for i = 0 to Array.length left - 1 do
	    let back = left.(i) in
	    let di = diff back right.(i) in
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	    guard di (fun s ->
			left.(i) <- diff back right.(i);
			aux rights s;
			left.(i) <- back;
		     ) s
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	  done
  in
  let rec start i s =
    if (i < 0) then aux rights s
    else
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      guard left.(i) (start (i - 1)) s
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  in
  start (Array.length left - 1) s


let is_empty d =
  let s = slot d in
  List.iter 
    (fun s' -> if s'.status = Maybe then s'.status <- Empty; s'.notify <- Nothing) 
    !marks;
  marks := [];
  s.status = Empty
  

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module Assumptions = Set.Make(struct type t = descr let compare = compare_descr end)
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let memo = ref Assumptions.empty
let cache_false = DescrHash.create 33000
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let rec empty_rec d =
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  if not (Intervals.is_empty d.ints) then false
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  else if not (Atoms.is_empty d.atoms) then false
  else if not (Chars.is_empty d.chars) then false
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  else if d.absent then false
565
566
  else if DescrHash.mem cache_false d then false 
  else if Assumptions.mem d !memo then true
567
568
  else (
    let backup = !memo in
569
    memo := Assumptions.add d backup;
570
    if 
571
572
573
      (empty_rec_times (BoolPair.get d.times)) &&
      (empty_rec_times (BoolPair.get d.xml)) &&
      (empty_rec_arrow (BoolPair.get d.arrow)) &&
574
575
576
577
      (empty_rec_record d.record) 
    then true
    else (
      memo := backup;
578
      DescrHash.add cache_false d ();
579
580
581
582
583
584
585
586
587
588
      false
    )
  )

and empty_rec_times c =
  List.for_all empty_rec_times_aux c

and empty_rec_times_aux (left,right) =
  let rec aux accu1 accu2 = function
    | (t1,t2)::right ->
589
590
	if trivially_empty (cap_t accu1 t1) || 
	   trivially_empty (cap_t accu2 t2) then
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592
593
594
595
	  aux accu1 accu2 right
	else
          let accu1' = diff_t accu1 t1 in
          if not (empty_rec accu1') then aux accu1' accu2 right;
          let accu2' = diff_t accu2 t2 in
596
	  if not (empty_rec accu2') then aux accu1 accu2' right
597
598
599
600
601
    | [] -> raise NotEmpty
  in
  let (accu1,accu2) = cap_product left in
  (empty_rec accu1) || (empty_rec accu2) ||
    (try aux accu1 accu2 right; true with NotEmpty -> false)
602

603
604
605
606
607
608
609
610
611

and empty_rec_arrow c =
  List.for_all empty_rec_arrow_aux c

and empty_rec_arrow_aux (left,right) =
  let single_right (s1,s2) =
    let rec aux accu1 accu2 = function
      | (t1,t2)::left ->
          let accu1' = diff_t accu1 t1 in
612
          if not (empty_rec accu1') then aux accu1' accu2 left;
613
          let accu2' = cap_t accu2 t2 in
614
          if not (empty_rec accu2') then aux accu1 accu2' left
615
616
617
618
619
620
621
622
      | [] -> raise NotEmpty
    in
    let accu1 = descr s1 in
    (empty_rec accu1) ||
    (try aux accu1 (diff any (descr s2)) left; true with NotEmpty -> false)
  in
  List.exists single_right right

623
and empty_rec_record_aux (labels,(oleft,left),rights) =
624
625
  let rec aux = function
    | [] -> raise NotEmpty
626
    | (oright,right)::rights ->
627
628
629
630
	let next =
	  (oleft && (not oright)) ||
	  exists (Array.length left)
	    (fun i ->
631
	       trivially_empty (cap left.(i) right.(i)))
632
633
634
635
636
637
	in
	if next then aux rights 
	else
	  for i = 0 to Array.length left - 1 do
	    let back = left.(i) in
	    let di = diff back right.(i) in
638
	    if not (empty_rec di) then (
639
640
641
642
643
644
645
	      left.(i) <- diff back right.(i);
	      aux rights;
	      left.(i) <- back;
	    )
	  done
  in
  exists (Array.length left) 
646
    (fun i -> empty_rec left.(i))
647
648
649
650
  ||
  (try aux rights; true with NotEmpty -> false)
	    

651
and empty_rec_record c =
652
  List.for_all empty_rec_record_aux (get_record c)
653

654
655
(*
let is_empty d =
656
  empty_rec d
657
  *)  
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685

let non_empty d = 
  not (is_empty d)

let subtype d1 d2 =
  is_empty (diff d1 d2)

module Product =
struct
  type t = (descr * descr) list

  let other ?(kind=`Normal) d = 
    match kind with
      | `Normal -> { d with times = empty.times }
      | `XML -> { d with xml = empty.xml }

  let is_product ?kind d = is_empty (other ?kind d)

  let need_second = function _::_::_ -> true | _ -> false

  let normal_aux d =
    let res = ref [] in

    let add (t1,t2) =
      let rec loop t1 t2 = function
	| [] -> res := (ref (t1,t2)) :: !res
	| ({contents = (d1,d2)} as r)::l ->
	    (*OPT*) 
686
(*	    if equal_descr d1 t1 then r := (d1,cup d2 t2) else*)
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
	      
	      let i = cap t1 d1 in
	      if is_empty i then loop t1 t2 l
	      else (
		r := (i, cup t2 d2);
		let k = diff d1 t1 in 
		if non_empty k then res := (ref (k,d2)) :: !res;
		
		let j = diff t1 d1 in 
		if non_empty j then loop j t2 l
	      )
      in
      loop t1 t2 !res
    in
    List.iter add d;
    List.map (!) !res

704
(*
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
This version explodes when dealing with
   Any - [ t1? t2? t3? ... tn? ]
==> need partitioning 
*)
  let get_aux d =
    let line accu (left,right) =
      let rec aux accu d1 d2 = function
	| (t1,t2)::right ->
	    let accu = 
	      let d1 = diff_t d1 t1 in
              if is_empty d1 then accu else aux accu d1 d2 right in
	    let accu =
              let d2 = diff_t d2 t2 in
              if is_empty d2 then accu else aux accu d1 d2 right in
	    accu
	| [] -> (d1,d2) :: accu
      in
      let (d1,d2) = cap_product left in
      if (is_empty d1) || (is_empty d2) then accu else aux accu d1 d2 right
    in
    List.fold_left line [] d

(* Partitioning:

(t,s) - ((t1,s1) | (t2,s2) | ... | (tn,sn))
=
(t & t1, s - s1) | ... | (t & tn, s - sn) | (t - (t1|...|tn), s)

733
*)
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
  let get_aux d =
    let accu = ref [] in
    let line (left,right) =
      let (d1,d2) = cap_product left in
      if (non_empty d1) && (non_empty d2) then
	let right = List.map (fun (t1,t2) -> descr t1, descr t2) right in
	let right = normal_aux right in
	let resid1 = ref d1 in
	let () = 
	  List.iter
	    (fun (t1,t2) ->
	       let t1 = cap d1 t1 in
	       if (non_empty t1) then
		 let () = resid1 := diff !resid1 t1 in
		 let t2 = diff d2 t2 in
		 if (non_empty t2) then accu := (t1,t2) :: !accu
	    ) right in
	if non_empty !resid1 then accu := (!resid1, d2) :: !accu 
    in
753
    List.iter line (BoolPair.get d);
754
    !accu
755
756
757
(* Maybe, can improve this function with:
     (t,s) \ (t1,s1) = (t&t',s\s') | (t\t',s),
   don't call normal_aux *)
758

759

760
761
  let get ?(kind=`Normal) d = 
    match kind with
762
763
      | `Normal -> get_aux d.times
      | `XML -> get_aux d.xml
764
765
766

  let pi1 = List.fold_left (fun acc (t1,_) -> cup acc t1) empty
  let pi2 = List.fold_left (fun acc (_,t2) -> cup acc t2) empty
767
768
769
770
  let pi2_restricted restr = 
    List.fold_left (fun acc (t1,t2) -> 
		      if is_empty (cap t1 restr) then acc
		      else cup acc t2) empty
771
772

  let restrict_1 rects pi1 =
773
774
    let aux acc (t1,t2) = 
      let t1 = cap t1 pi1 in if is_empty t1 then acc else (t1,t2)::acc in
775
776
777
778
    List.fold_left aux [] rects
  
  type normal = t

779
  module Memo = Map.Make(struct type t = descr BoolPair.t let compare = BoolPair.compare end)
780
781
782
783
784
785
786
787


  let memo = ref Memo.empty
  let normal ?(kind=`Normal) d = 
    let d = match kind with `Normal -> d.times | `XML -> d.xml in
    try Memo.find d !memo 
    with
	Not_found ->
788
	  let gd = get_aux d in
789
	  let n = normal_aux gd in
790
791
(* Could optimize this call to normal_aux because one already
   know that each line is normalized ... *)
792
793
	  memo := Memo.add d n !memo;
	  n
794

795
796
797
798
  let any = { empty with times = any.times }
  and any_xml = { empty with xml = any.xml }
  let is_empty d = d = []
end
799

800
801
module Print = 
struct
802
803
804
805
806
807
808
  let rec print_union ppf = function
    | [] -> Format.fprintf ppf "Empty"
    | [h] -> h ppf
    | h::t -> Format.fprintf ppf "@[%t |@ %a@]" h print_union t

  let print_tag ppf a =
    match Atoms.is_atom a with
809
810
      | Some a -> Format.fprintf ppf "%s" (Atoms.value a)
      | None -> Format.fprintf ppf "(%a)" print_union (Atoms.print a)
811

812
  let print_const ppf = function
813
814
815
    | Integer i -> Intervals.print_v ppf i
    | Atom a -> Atoms.print_v ppf a
    | Char c -> Chars.print_v ppf c
816

817
818
819
  let named = State.ref "Types.Printf.named" DescrMap.empty
  let register_global name d = 
    named := DescrMap.add d name !named
820
821
822
823
824
825
826
827
828
829

  let marks = DescrHash.create 63
  let wh = ref []
  let count_name = ref 0
  let name () =
    incr count_name;
    "X" ^ (string_of_int !count_name)
(* TODO: 
   check that these generated names does not conflict with declared types *)

830
  let trivial_rec b = b = BoolRec.empty || b = BoolRec.full
831
  let trivial_pair b = b = BoolPair.empty || b = BoolPair.full
832
833

  let worth_abbrev d = 
834
835
    not (trivial_pair d.times && trivial_pair d.xml && 
	 trivial_pair d.arrow && trivial_rec d.record) 
836
837
838

  let rec mark n = mark_descr (descr n)
  and mark_descr d =
839
    if not (DescrMap.mem d !named) then
840
841
842
843
844
845
846
847
      try 
	let r = DescrHash.find marks d in
	if (!r = None) && (worth_abbrev d) then 
	  let na = name () in 
	  r := Some na;
	  wh := (na,d) :: !wh
      with Not_found -> 
	DescrHash.add marks d (ref None);
848
849
    	BoolPair.iter (fun (n1,n2) -> mark n1; mark n2) d.times;
    	BoolPair.iter 
850
851
	  (fun (n1,n2) -> mark n1; mark n2
(*
852
853
854
	     List.iter
	       (fun (d1,d2) ->
		  mark_descr d2;
855
856
857
    		  bool_iter 
		    (fun (o,l) -> List.iter (fun (l,(o,n)) -> mark n) l) 
		    d1.record
858
		  let l = get_record d1.record in
859
860
861
862
863
		  List.iter (fun labs,(_,(_,p)),ns ->
			       Array.iter mark_descr p;
			       List.iter (fun (_,(_,n)) -> 
					    Array.iter mark_descr n) ns
			    ) l
864
865
	       )
	       (Product.normal (descr n2))
866
*)
867
	  ) d.xml;
868
	BoolPair.iter (fun (n1,n2) -> mark n1; mark n2) d.arrow;
869
870
871
    	BoolRec.iter 
	  (fun (o,l) -> List.iter (fun (l,n) -> mark n) (LabelMap.get l)) 
	  d.record
872
873
874
875
876

    
  let rec print ppf n = print_descr ppf (descr n)
  and print_descr ppf d = 
    try 
877
      let name = DescrMap.find d !named in
878
879
880
881
882
883
884
      Format.fprintf ppf "%s" name
    with Not_found ->
      try
      	match !(DescrHash.find marks d) with
      	  | Some n -> Format.fprintf ppf "%s" n
      	  | None -> real_print_descr ppf d
      with
885
	  Not_found -> assert false
886
887
  and real_print_descr ppf d = 
    if d = any then Format.fprintf ppf "Any" else
888
889
890
891
892
893
894
895
896
      (
	if d.absent then Format.fprintf ppf "?";
	print_union ppf 
	  (Intervals.print d.ints @
	   Chars.print d.chars @
	   Atoms.print d.atoms @
	   BoolPair.print "Pair" print_times d.times @
	   BoolPair.print "XML" print_xml d.xml @
	   BoolPair.print "Arrow" print_arrow d.arrow @
897
	   BoolRec.print "Record" print_record d.record
898
899
	  )
      )
900
901
  and print_times ppf (t1,t2) =
    Format.fprintf ppf "@[(%a,%a)@]" print t1 print t2
902
  and print_xml ppf (t1,t2) =
903
904
    Format.fprintf ppf "@[XML(%a,%a)@]" print t1 print t2
(*
905
906
907
908
909
910
911
912
913
    let l = Product.normal (descr t2) in
    let l = List.map
	      (fun (d1,d2) ppf ->
		 Format.fprintf ppf "@[<><%a%a>%a@]" 
		   print_tag (descr t1).atoms
		   print_attribs d1.record 
		   print_descr d2) l
    in
    print_union ppf l
914
*)
915
916
  and print_arrow ppf (t1,t2) =
    Format.fprintf ppf "@[(%a -> %a)@]" print t1 print t2
917
918
919
920
  and print_record ppf (o,r) =
    let o = if o then "" else "|" in
    Format.fprintf ppf "@[{%s" o;
    let first = ref true in
921
    List.iter (fun (l,t) ->
922
		 let sep = if !first then (first := false; "") else ";" in
923
924
		 Format.fprintf ppf "%s@ @[%s =@] %a" sep
		   (LabelPool.value l) print t
925
	      ) (LabelMap.get r);
926
927
    Format.fprintf ppf " %s}@]" o
(*
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
  and print_attribs ppf r =
    let l = get_record r in
    if l <> [ [] ] then 
    let l = List.map 
      (fun att ppf ->
	 let first = ref true in
	 Format.fprintf ppf "{" ;
	 List.iter (fun (l,(o,d)) ->
		      Format.fprintf ppf "%s%s=%s%a" 
		        (if !first then "" else " ")
		        (LabelPool.value l) (if o then "?" else "")
		        print_descr d; 
		      first := false
		   ) att;
	   Format.fprintf ppf "}"
      ) l in
    print_union ppf l
945
*)
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972

	  
  let end_print ppf =
    (match List.rev !wh with
       | [] -> ()
       | (na,d)::t ->
	   Format.fprintf ppf " where@ @[%s = %a" na real_print_descr d;
	   List.iter 
	     (fun (na,d) -> 
		Format.fprintf ppf " and@ %s = %a" na real_print_descr d)
	     t;
	   Format.fprintf ppf "@]"
    );
    Format.fprintf ppf "@]";
    count_name := 0;
    wh := [];
    DescrHash.clear marks

  let print_descr ppf d =
    mark_descr d;
    Format.fprintf ppf "@[%a" print_descr d;
    end_print ppf

   let print ppf n = print_descr ppf (descr n)

end

973
let () = print_descr := Print.print_descr
974

975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
module Positive =
struct
  type rhs = [ `Type of descr | `Cup of v list | `Times of v * v ]
  and v = { mutable def : rhs; mutable node : node option }


  let rec make_descr seen v =
    if List.memq v seen then empty
    else
      let seen = v :: seen in
      match v.def with
	| `Type d -> d
	| `Cup vl -> 
	    List.fold_left (fun acc v -> cup acc (make_descr seen v)) empty vl
	| `Times (v1,v2) -> times (make_node v1) (make_node v2)

  and make_node v =
    match v.node with
      | Some n -> n
      | None ->
	  let n = make () in
	  v.node <- Some n;
	  let d = make_descr [] v in
	  define n d;
	  n

  let forward () = { def = `Cup []; node = None }
  let def v d = v.def <- d
  let cons d = let v = forward () in def v d; v
  let ty d = cons (`Type d)
  let cup vl = cons (`Cup vl)
  let times d1 d2 = cons (`Times (d1,d2))
  let define v1 v2 = def v1 (`Cup [v2]) 

  let solve v = internalize (make_node v)
end




(* Sample value *)
module Sample =
struct

1019

1020
1021
1022
1023
1024
let rec find f = function
  | [] -> raise Not_found
  | x::r -> try f x with Not_found -> find f r

type t =
1025
1026
1027
  | Int of Intervals.v
  | Atom of Atoms.v
  | Char of Chars.v
1028
1029
  | Pair of (t * t)
  | Xml of (t * t)
1030
1031
  | Record of (label * t) list
  | Fun of (node * node) list
1032
  | Other
1033
  exception FoundSampleRecord of (label * t) list
1034
1035
1036
1037
1038

let rec sample_rec memo d =
  if (Assumptions.mem d memo) || (is_empty d) then raise Not_found 
  else 
    try Int (Intervals.sample d.ints) with Not_found ->
1039
    try Atom (Atoms.sample d.atoms) with 
1040
1041
	Not_found ->
(* Here: could create a fresh atom ... *)
1042
    try Char (Chars.sample d.chars) with Not_found ->
1043
    try sample_rec_arrow (BoolPair.get d.arrow) with Not_found ->
1044
1045

    let memo = Assumptions.add d memo in
1046
1047
    try Pair (sample_rec_times memo (BoolPair.get d.times)) with Not_found ->
    try Xml (sample_rec_times memo (BoolPair.get d.xml)) with Not_found ->
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
    try sample_rec_record memo d.record with Not_found -> 
    raise Not_found


and sample_rec_times memo c = 
  find (sample_rec_times_aux memo) c

and sample_rec_times_aux memo (left,right) =
  let rec aux accu1 accu2 = function
    | (t1,t2)::right ->
1058
1059
(*TODO: check: is this correct ?  non_empty could return true
  but because of coinduction, the call to aux may raise Not_found, no ? *)
1060
1061
1062
1063
1064
        let accu1' = diff_t accu1 t1 in
        if non_empty accu1' then aux accu1' accu2 right else
          let accu2' = diff_t accu2 t2 in
          if non_empty accu2' then aux accu1 accu2' right else
	    raise Not_found
1065
    | [] -> (sample_rec memo accu1, sample_rec memo accu2)
1066
1067
1068
1069
1070
1071
1072
1073
  in
  let (accu1,accu2) = cap_product left in
  if (is_empty accu1) || (is_empty accu2) then raise Not_found;
  aux accu1 accu2 right

and sample_rec_arrow c =
  find sample_rec_arrow_aux c

1074
1075
1076
1077
1078
1079
1080
1081
and check_empty_simple_arrow_line left (s1,s2) = 
  let rec aux accu1 accu2 = function
    | (t1,t2)::left ->
        let accu1' = diff_t accu1 t1 in
        if non_empty accu1' then aux accu1 accu2 left;
        let accu2' = cap_t accu2 t2 in
        if non_empty accu2' then aux accu1 accu2 left
    | [] -> raise NotEmpty
1082
  in
1083
1084
1085
1086
1087
1088
1089
1090
1091
  let accu1 = descr s1 in
  (is_empty accu1) ||
  (try aux accu1 (diff any (descr s2)) left; true with NotEmpty -> false)

and check_empty_arrow_line left right = 
  List.exists (check_empty_simple_arrow_line left) right

and sample_rec_arrow_aux (left,right) =
  if (check_empty_arrow_line left right) then raise Not_found
1092
1093
1094
1095
1096
1097
  else Fun left


and sample_rec_record memo c =
  Record (find (sample_rec_record_aux memo) (get_record c))

1098
and sample_rec_record_aux memo (labels,(oleft,left),rights) =
1099
1100
1101
1102
  let rec aux = function
    | [] -> 
	let l = ref labels and fields = ref [] in
	for i = 0 to Array.length left - 1 do
1103
	  fields := (List.hd !l, sample_rec memo left.(i))::!fields;
1104
1105
1106
	  l := List.tl !l
	done;
	raise (FoundSampleRecord (List.rev !fields))
1107
    | (oright,right)::rights ->
1108
1109
1110
1111
1112
1113
	let next = (oleft && (not oright)) in
	if next then aux rights 
	else
	  for i = 0 to Array.length left - 1 do
	    let back = left.(i) in
	    let di = diff back right.(i) in
1114
	    if not (is_empty di) then (
1115
1116
1117
1118
1119
1120
1121
	      left.(i) <- diff back right.(i);
	      aux rights;
	      left.(i) <- back;
	    )
	  done
  in
  if exists (Array.length left) 
1122
    (fun i -> is_empty left.(i)) then raise Not_found;
1123
1124
1125
1126
1127
1128
  try aux rights; raise Not_found
  with FoundSampleRecord r -> r

	    


1129

1130
let get x = try sample_rec Assumptions.empty x with Not_found -> Other
1131

1132
1133
1134
1135
1136
1137
1138
  let rec print_sep f sep ppf = function
    | [] -> ()
    | [x] -> f ppf x
    | x::rem -> f ppf x; Format.fprintf ppf "%s" sep; print_sep f sep ppf rem


  let rec print ppf = function
1139
1140
1141
    | Int i -> Intervals.print_v ppf i
    | Atom a -> Atoms.print_v ppf a
    | Char c -> Chars.print_v ppf c
1142
    | Pair (x1,x2) -> Format.fprintf ppf "(%a,%a)" print x1 print x2
1143
    | Xml (x1,x2) -> Format.fprintf ppf "XML(%a,%a)" print x1 print x2
1144
1145
1146
1147
1148
    | Record r ->
	Format.fprintf ppf "{ %a }"
	  (print_sep 
	     (fun ppf (l,x) -> 
		Format.fprintf ppf "%s = %a"
1149
		(LabelPool.value l)
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
		print x
	     )
	     " ; "
	  ) r
    | Fun iface ->
	Format.fprintf ppf "(fun ( %a ) x -> ...)"
	  (print_sep
	     (fun ppf (t1,t2) ->
		Format.fprintf ppf "%a -> %a; "
		Print.print t1 Print.print t2
	     )
	     " ; "
	  ) iface
1163
1164
    | Other ->
	Format.fprintf ppf "[cannot determine value]"
1165
1166
1167
1168
1169
1170
end



module Record = 
struct
1171
1172
1173
1174
  let has_record d = not (is_empty { empty with record = d.record })
  let or_absent d = { d with absent = true }
  let any_or_absent = or_absent any
  let has_absent d = d.absent
1175

1176
1177
  module T = struct
    type t = descr
1178
    let any = any_or_absent
1179
1180
1181
    let cap = cap
    let cup = cup
    let diff = diff
1182
1183
    let is_empty = is_empty
    let empty = empty
1184
1185
  end
  module R = struct
1186
1187
1188
1189
1190
1191
1192
    type t = descr
    let any = { empty with record = any.record }
    let cap = cap
    let cup = cup
    let diff = diff
    let is_empty = is_empty
    let empty = empty
1193
1194
1195
  end
  module TR = Normal.Make(T)(R)

1196
1197
1198
1199
1200
1201
1202
  let any_record = { empty with record = BoolRec.full }

  let atom o l = 
    if o && LabelMap.is_empty l then any_record else
    { empty with record = BoolRec.atom (o,l) }

  type zor = Pair of descr * descr | Any | Empty
1203

1204
  let aux d l=
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
    let f (o,r) =
      try
	let (lt,rem) = LabelMap.assoc_remove l r in
	Pair (descr lt, atom o rem)
      with Not_found -> 
	if o then
	  if LabelMap.is_empty r then Any else
	    Pair (any_or_absent, { empty with record = BoolRec.atom (o,r) })
	else Empty
    in
    List.fold_left 
      (fun b (p,n) ->
	 let rec aux_p accu = function
	   | x::p -> 
	       (match f x with
		  | Pair (t1,t2) -> aux_p ((t1,t2)::accu) p
		  | Any -> aux_p accu p
		  | Empty -> b)
	   | [] -> aux_n accu [] n
	 and aux_n p accu = function
	   | x::n -> 
	       (match f x with
		  | Pair (t1,t2) -> aux_n p ((t1,t2)::accu) n
		  | Empty -> aux_n p accu n
		  | Any -> b)
	   | [] -> (p,accu) :: b in
	 aux_p [] p)
      []
      (BoolRec.get d.record)
1234

1235
1236
  let split (d : descr) l =
    TR.boolean (aux d l)
1237

1238
1239
  let split_normal d l =
    TR.boolean_normal (aux d l)
1240