65 lines
3.1 KiB
OCaml
65 lines
3.1 KiB
OCaml
(***********************************************************************)
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(* *)
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(* Objective Caml *)
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(* *)
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(* Damien Doligez, projet Para, INRIA Rocquencourt *)
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(* *)
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(* Copyright 1997 Institut National de Recherche en Informatique et *)
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(* en Automatique. All rights reserved. This file is distributed *)
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(* under the terms of the GNU Library General Public License. *)
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(* *)
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(***********************************************************************)
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(* $Id$ *)
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(* Module [Weak]: arrays of weak pointers *)
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type 'a t;;
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(* The type of arrays of weak pointers (weak arrays). A weak
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pointer is an object that the garbage collector may erase at
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any time.
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A weak pointer is said to be full if it points to an object,
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empty if the object was erased by the GC.
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*)
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val create : len:int -> 'a t;;
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(* [Weak.create n] returns a new weak array of length [n].
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All the pointers are initially empty.
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*)
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val length : 'a t -> int;;
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(* [Weak.length ar] returns the length (number of elements) of
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[ar].
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*)
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val set : 'a t -> pos:int -> 'a option -> unit;;
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(* [Weak.set ar n (Some el)] sets the [n]th cell of [ar] to be a
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(full) pointer to [el]; [Weak.set ar n None] sets the [n]th
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cell of [ar] to empty.
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Raise [Invalid_argument "Weak.set"] if [n] is not in the range
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0 to [Weak.length a - 1].
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*)
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val get : 'a t -> pos:int -> 'a option;;
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(* [Weak.get ar n] returns None if the [n]th cell of [ar] is
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empty, [Some x] (where [x] is the object) if it is full.
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Raise [Invalid_argument "Weak.get"] if [n] is not in the range
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0 to [Weak.length a - 1].
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*)
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val check: 'a t -> pos:int -> bool;;
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(* [Weak.check ar n] returns [true] if the [n]th cell of [ar] is
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full, [false] if it is empty. Note that even if [Weak.check ar n]
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returns [true], a subsequent [Weak.get ar n] can return [None].
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*)
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val fill: 'a t -> pos:int -> len:int -> 'a option -> unit;;
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(* [Weak.fill ar ofs len el] sets to [el] all pointers of [ar] from
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[ofs] to [ofs + len - 1]. Raise [Invalid_argument "Weak.fill"]
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if [ofs] and [len] do not designate a valid subarray of [a].
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*)
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val blit : src:'a t -> src_pos:int ->
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dst:'a t -> dst_pos:int -> len:int -> unit;;
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(* [Weak.blit ar1 off1 ar2 off2 len] copies [len] weak pointers
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from [ar1] (starting at [off1]) to [ar2] (starting at [off2]).
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It works correctly even if [ar1] and [ar2] are the same.
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Raise [Invalid_argument "Weak.blit"] if [off1] and [len] do
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not designate a valid subarray of [ar1], or if [off2] and [len]
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do not designate a valid subarray of [ar2].
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*)
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