Module Core_kernel.Fqueue

A simple polymorphic functional queue. Use this data structure for strictly first-in, first-out access to a sequence of values. For a similar data structure with enqueue and dequeue accessors on both ends of a sequence, see Core_kernel.Fdeque.

Amortized running times assume that enqueue/dequeue are used sequentially, threading the changing Fqueue through the calls.

type 'a t
include sig ... end
val bin_read_t : 'a Bin_prot.Read.reader ‑> 'a t Bin_prot.Read.reader
val bin_size_t : 'a Bin_prot.Size.sizer ‑> 'a t Bin_prot.Size.sizer
val bin_write_t : 'a Bin_prot.Write.writer ‑> 'a t Bin_prot.Write.writer
val bin_shape_t : Bin_prot.Shape.t ‑> Bin_prot.Shape.t
val compare : ('a ‑> 'a ‑> Core_kernel__.Import.int) ‑> 'a t ‑> 'a t ‑> Core_kernel__.Import.int
val hash_fold_t : (Base.Hash.state ‑> 'a ‑> Base.Hash.state) ‑> Base.Hash.state ‑> 'a t ‑> Base.Hash.state
val t_of_sexp : (Base.Sexp.t ‑> 'a) ‑> Base.Sexp.t ‑> 'a t
val sexp_of_t : ('a ‑> Base.Sexp.t) ‑> 'a t ‑> Base.Sexp.t
include Container.S1 with type t := a t
type 'a t
val mem : 'a t ‑> 'a ‑> equal:('a ‑> 'a ‑> bool) ‑> bool

Checks whether the provided element is there, using equal.

val length : 'a t ‑> int
val is_empty : 'a t ‑> bool
val iter : 'a t ‑> f:('a ‑> unit) ‑> unit
val fold : 'a t ‑> init:'accum ‑> f:('accum ‑> 'a ‑> 'accum) ‑> 'accum

fold t ~init ~f returns f (... f (f (f init e1) e2) e3 ...) en, where e1..en are the elements of t

val fold_result : 'a t ‑> init:'accum ‑> f:('accum ‑> 'a ‑> ('accum'eBase.Result.t) ‑> ('accum'eBase.Result.t

fold_result t ~init ~f is a short-circuiting version of fold that runs in the Result monad. If f returns an Error _, that value is returned without any additional invocations of f.

val fold_until : 'a t ‑> init:'accum ‑> f:('accum ‑> 'a ‑> ('accum'finalBase__.Container_intf.Continue_or_stop.t) ‑> finish:('accum ‑> 'final) ‑> 'final

fold_until t ~init ~f ~finish is a short-circuiting version of fold. If f returns Stop _ the computation ceases and results in that value. If f returns Continue _, the fold will proceed. If f never returns Stop _, the final result is computed by finish.

val exists : 'a t ‑> f:('a ‑> bool) ‑> bool

Returns true if and only if there exists an element for which the provided function evaluates to true. This is a short-circuiting operation.

val for_all : 'a t ‑> f:('a ‑> bool) ‑> bool

Returns true if and only if the provided function evaluates to true for all elements. This is a short-circuiting operation.

val count : 'a t ‑> f:('a ‑> bool) ‑> int

Returns the number of elements for which the provided function evaluates to true.

val sum : (module Base.Commutative_group.S with type t = 'sum) ‑> 'a t ‑> f:('a ‑> 'sum) ‑> 'sum

Returns the sum of f i for all i in the container.

val find : 'a t ‑> f:('a ‑> bool) ‑> 'a option

Returns as an option the first element for which f evaluates to true.

val find_map : 'a t ‑> f:('a ‑> 'b option) ‑> 'b option

Returns the first evaluation of f that returns Some, and returns None if there is no such element.

val to_list : 'a t ‑> 'a list
val to_array : 'a t ‑> 'a array
val min_elt : 'a t ‑> compare:('a ‑> 'a ‑> int) ‑> 'a option

Returns a minimum (resp maximum) element from the collection using the provided compare function, or None if the collection is empty. In case of a tie, the first element encountered while traversing the collection is returned. The implementation uses fold so it has the same complexity as fold.

val max_elt : 'a t ‑> compare:('a ‑> 'a ‑> int) ‑> 'a option
include Core_kernel__.Import.Invariant.S1 with type t := a t
type 'a t
include Core_kernel__.Import.Monad.S with type t := a t
type 'a t
include Base__.Monad_intf.S_without_syntax with type t := a t
type 'a t
include Base__.Monad_intf.Infix with type t := a t
type 'a t
val (>>=) : 'a t ‑> ('a ‑> 'b t) ‑> 'b t

t >>= f returns a computation that sequences the computations represented by two monad elements. The resulting computation first does t to yield a value v, and then runs the computation returned by f v.

val (>>|) : 'a t ‑> ('a ‑> 'b) ‑> 'b t

t >>| f is t >>= (fun a -> return (f a)).

module Monad_infix : Base__.Monad_intf.Infix with type t := a t
val bind : 'a t ‑> f:('a ‑> 'b t) ‑> 'b t

bind t ~f = t >>= f

val return : 'a ‑> 'a t

return v returns the (trivial) computation that returns v.

val map : 'a t ‑> f:('a ‑> 'b) ‑> 'b t

map t ~f is t >>| f.

val join : 'a t t ‑> 'a t

join t is t >>= (fun t' -> t').

val ignore_m : 'a t ‑> unit t

ignore_m t is map t ~f:(fun _ -> ()). ignore_m used to be called ignore, but we decided that was a bad name, because it shadowed the widely used Pervasives.ignore. Some monads still do let ignore = ignore_m for historical reasons.

val all : 'a t list ‑> 'a list t
val all_unit : unit t list ‑> unit t
val all_ignore : unit t list ‑> unit t
  • Deprecated [since 2018-02] Use [all_unit]
include Base__.Monad_intf.Syntax with type t := a t
type 'a t
module Let_syntax : sig ... end
val empty : 'a t

The empty queue.

val enqueue : 'a t ‑> 'a ‑> 'a t

enqueue t x returns a queue with adds x to the end of t. Complexity: O(1).

val enqueue_top : 'a t ‑> 'a ‑> 'a t

Enqueues a single element on the *top* of the queue. Complexity: amortized O(1) enqueue_top is deprecated, use Fdeque.t instead.

val bot_exn : 'a t ‑> 'a

Returns the bottom (most recently enqueued) element. Raises Empty if no element is found. Complexity: O(1).

bot_exn is deprecated, use Fdeque.t instead.

val bot : 'a t ‑> 'a Core_kernel__.Import.option

Like bot_exn, but returns its result optionally, without exception. Complexity: O(1).

bot is deprecated, use Fdeque.t instead.

val top_exn : 'a t ‑> 'a

Like bot_exn, except returns top (least recently enqueued) element. Complexity: O(1).

val top : 'a t ‑> 'a Core_kernel__.Import.option

Like top_exn, but returns its result optionally, without exception, Complexity: O(1).

val dequeue_exn : 'a t ‑> 'a * 'a t

dequeue_exn t removes and returns the front of t, raising Empty if t is empty. Complexity: amortized O(1)

val dequeue : 'a t ‑> ('a * 'a t) Core_kernel__.Import.option

Like dequeue_exn, but returns result optionally, without exception. Complexity: amortized O(1)

val discard_exn : 'a t ‑> 'a t

Returns version of queue with top element removed. Complexity: amortized O(1).

val to_list : 'a t ‑> 'a Core_kernel__.Import.list

to_list t returns a list of the elements in t in order from least-recently-added (at the head) to most-recently-added (at the tail). Complexity: O(n).

val of_list : 'a Core_kernel__.Import.list ‑> 'a t

of_list is the inverse of to_list. Complexity: O(n).

val length : 'a t ‑> Core_kernel__.Import.int

Complexity: O(1).

val is_empty : 'a t ‑> Core_kernel__.Import.bool

Complexity: O(1).

val singleton : 'a ‑> 'a t
module Stable : sig ... end