29 lines
1.1 KiB
OCaml
29 lines
1.1 KiB
OCaml
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(* 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 new: 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], from the
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least recently entered to the most recently entered.
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The queue itself is unchanged. *)
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