1 files changed, 28 insertions, 0 deletions
diff --git a/stdlib/queue.mli b/stdlib/queue.mli
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+++ b/stdlib/queue.mli
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+(* Queues *)
+
+(* This module implements queues (FIFOs), with in-place modification. *)
+
+type 'a t
+        (* The type of queues containing elements of type ['a]. *)
+
+exception Empty
+        (* Raised when [take] is applied to an empty queue. *)
+
+val new: unit -> 'a t
+        (* Return a new queue, initially empty. *)
+val add: 'a -> 'a t -> unit
+        (* [add x q] adds the element [x] at the end of the queue [q]. *)
+val take: 'a t -> 'a
+        (* [take q] removes and returns the first element in queue [q],
+           or raises [Empty] if the queue is empty. *)
+val 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. *)
+val clear : 'a t -> unit
+        (* Discard all elements from a queue. *)
+val length: 'a t -> int
+        (* Return the number of elements in a queue. *)
+val 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. *)