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Text File | 1993-09-24 | 1.1 KB | 30 lines | [TEXT/MPS ] |
- (* Queues *)
-
- (* This module implements queues (FIFOs), with in-place modification. *)
-
- type 'a t mutable;;
- (* The type of queues containing elements of type ['a]. *)
-
- exception Empty;;
- (* Raised when [take] is applied to an empty queue. *)
-
- value new: unit -> 'a t
- (* Return a new queue, initially empty. *)
- and add: 'a -> 'a t -> unit
- (* [add x q] adds the element [x] at the end of the queue [q]. *)
- and take: 'a t -> 'a
- (* [take q] removes and returns the first element in queue [q],
- or raises [Empty] if the queue is empty. *)
- and peek: 'a t -> 'a
- (* [peek q] returns the first element in queue [q], without removing
- it from the queue, or raises [Empty] if the queue is empty. *)
- and clear : 'a t -> unit
- (* Discard all elements from a queue. *)
- and length: 'a t -> int
- (* Return the number of elements in a queue. *)
- and iter: ('a -> 'b) -> 'a t -> unit
- (* [iter f q] applies [f] in turn to all elements of [q], from the
- least recently entered to the most recently entered.
- The queue itself is unchanged. *)
- ;;
-