diff options
Diffstat (limited to 'lib/hashcons.ml')
| -rw-r--r-- | lib/hashcons.ml | 43 |
1 files changed, 7 insertions, 36 deletions
diff --git a/lib/hashcons.ml b/lib/hashcons.ml index 144d9513..4eaacf91 100644 --- a/lib/hashcons.ml +++ b/lib/hashcons.ml @@ -15,7 +15,7 @@ * of objects of type t (u usually has the form (t1->t1)*(t2->t2)*...). * [hashcons u x] is a function that hash-cons the sub-structures of x using * the hash-consing functions u provides. - * [equal] is a comparison function. It is allowed to use physical equality + * [eq] is a comparison function. It is allowed to use physical equality * on the sub-terms hash-consed by the hashcons function. * [hash] is the hash function given to the Hashtbl.Make function * @@ -27,7 +27,7 @@ module type HashconsedType = type t type u val hashcons : u -> t -> t - val equal : t -> t -> bool + val eq : t -> t -> bool val hash : t -> int end @@ -53,7 +53,7 @@ module Make (X : HashconsedType) : (S with type t = X.t and type u = X.u) = (* We create the type of hashtables for t, with our comparison fun. * An invariant is that the table never contains two entries equals - * w.r.t (=), although the equality on keys is X.equal. This is + * w.r.t (=), although the equality on keys is X.eq. This is * granted since we hcons the subterms before looking up in the table. *) module Htbl = Hashset.Make(X) @@ -72,7 +72,7 @@ module Make (X : HashconsedType) : (S with type t = X.t and type u = X.u) = end -(* A few usefull wrappers: +(* A few useful wrappers: * takes as argument the function [generate] above and build a function of type * u -> t -> t that creates a fresh table each time it is applied to the * sub-hcons functions. *) @@ -96,20 +96,6 @@ let recursive_hcons h f u = let () = loop := hrec in hrec -(* A set of global hashcons functions *) -let hashcons_resets = ref [] -let init() = List.iter (fun f -> f()) !hashcons_resets - -(* [register_hcons h u] registers the hcons function h, result of the above - * wrappers. It returns another hcons function that always uses the same - * table, which can be reinitialized by init() - *) -let register_hcons h u = - let hf = ref (h u) in - let reset() = hf := h u in - hashcons_resets := reset :: !hashcons_resets; - (fun x -> !hf x) - (* Basic hashcons modules for string and obj. Integers do not need be hashconsed. *) @@ -124,7 +110,7 @@ module Hlist (D:HashedType) = let hashcons (hrec,hdata) = function | x :: l -> hdata x :: hrec l | l -> l - let equal l1 l2 = + let eq l1 l2 = l1 == l2 || match l1, l2 with | [], [] -> true @@ -144,7 +130,7 @@ module Hstring = Make( type t = string type u = unit let hashcons () s =(* incr accesstr;*) s - external equal : string -> string -> bool = "caml_string_equal" "noalloc" + external eq : string -> string -> bool = "caml_string_equal" "noalloc" (** Copy from CString *) let rec hash len s i accu = if i = len then accu @@ -191,21 +177,6 @@ module Hobj = Make( type t = Obj.t type u = (Obj.t -> Obj.t) * unit let hashcons (hrec,_) = hash_obj hrec - let equal = comp_obj + let eq = comp_obj let hash = Hashtbl.hash end) - -(* Hashconsing functions for string and obj. Always use the same - * global tables. The latter can be reinitialized with init() - *) -(* string : string -> string *) -(* obj : Obj.t -> Obj.t *) -let string = register_hcons (simple_hcons Hstring.generate Hstring.hcons) () -let obj = register_hcons (recursive_hcons Hobj.generate Hobj.hcons) () - -(* The unsafe polymorphic hashconsing function *) -let magic_hash (c : 'a) = - init(); - let r = obj (Obj.repr c) in - init(); - (Obj.magic r : 'a) |