42 lines
1.9 KiB
OCaml
42 lines
1.9 KiB
OCaml
(***********************************************************************)
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(* *)
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(* Objective Caml *)
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(* *)
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(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
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(* *)
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(* Copyright 1996 Institut National de Recherche en Informatique et *)
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(* Automatique. Distributed only by permission. *)
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(* *)
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(***********************************************************************)
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(* $Id$ *)
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(* Module [Queue]: first-in first-out queues *)
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(* This module implements queues (FIFOs), with in-place modification. *)
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type 'a t
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(* The type of queues containing elements of type ['a]. *)
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exception Empty
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(* Raised when [take] is applied to an empty queue. *)
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val create: unit -> 'a t
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(* Return a new queue, initially empty. *)
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val add: 'a -> 'a t -> unit
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(* [add x q] adds the element [x] at the end of the queue [q]. *)
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val take: 'a t -> 'a
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(* [take q] removes and returns the first element in queue [q],
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or raises [Empty] if the queue is empty. *)
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val peek: 'a t -> 'a
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(* [peek q] returns the first element in queue [q], without removing
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it from the queue, or raises [Empty] if the queue is empty. *)
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val clear : 'a t -> unit
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(* Discard all elements from a queue. *)
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val length: 'a t -> int
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(* Return the number of elements in a queue. *)
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val iter: ('a -> 'b) -> 'a t -> unit
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(* [iter f q] applies [f] in turn to all elements of [q],
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from the least recently entered to the most recently entered.
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The queue itself is unchanged. *)
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