Module Dequeue

module Dequeue: sig .. end

A double ended queue that can shrink and expand on both ends.

An index is assigned to an element when it enters the queue, and the index of an element is static (i.e. an index refers to a distinct element until that element is removed from the queue, no matter how many intervening push/pop operations occur).

One consequence of this is that the minimum index may be < 0.

The "front" is the smallest valid index, while the "back" is the largest.

All operations are amortized O(1) with a small constant.

type 'a t

include Container.S1

val create : ?initial_length:int -> ?never_shrink:bool -> unit -> 'a t

val front_index : 'a t -> int option

front_index t return the index of the front item in t.

val front_index_exn : 'a t -> int

front_index_exn t throws an exception if t is empty, otherwise returns the index of the front item in t

val back_index : 'a t -> int option

back_index t return the index of the back item in t.

val back_index_exn : 'a t -> int

back_index_exn t throws an exception if t is empty, otherwise returns the index of the back item in t

val get : 'a t -> int -> 'a option

get t i return the element at index i. Return None if i is invalid.

val get_exn : 'a t -> int -> 'a

get_exn t i return the element at index i. Raise an exception if i is invalid.

val peek : 'a t -> [ `back | `front ] -> 'a option

peek t back_or_front return the value at the back or front of the dequeue without removing it.

val peek_front : 'a t -> 'a option

val peek_front_exn : 'a t -> 'a

val peek_back : 'a t -> 'a option

val peek_back_exn : 'a t -> 'a

val set_exn : 'a t -> int -> 'a -> unit

set_exn t i v mutate the element at i.

val iter' : 'a t -> [ `back_to_front | `front_to_back ] -> f:('a -> unit) -> unit

iter' t ~f iter over the elements of t.

val iteri : 'a t -> f:(int -> 'a -> unit) -> unit

iteri t ~f iter over the elements of t `front_to_back passing in the index.

val iteri' : 'a t ->
       [ `back_to_front | `front_to_back ] -> f:(int -> 'a -> unit) -> unit

iteri' t ~f as iter, but also passes in the index of the current element.

val fold' : 'a t ->
       [ `back_to_front | `front_to_back ] -> init:'b -> f:('b -> 'a -> 'b) -> 'b

fold' t ~init ~f fold over the elements of t

val foldi : 'a t -> init:'b -> f:(int -> 'b -> 'a -> 'b) -> 'b

foldi t ~init ~f as fold, but also passes in the index of the current element.

val foldi' : 'a t ->
       [ `back_to_front | `front_to_back ] ->
       init:'b -> f:(int -> 'b -> 'a -> 'b) -> 'b

foldi' t ~init ~f as fold', but also passes in the index of the current element to f.

val enqueue : 'a t -> [ `back | `front ] -> 'a -> unit

enqueue t back_or_front v push v onto the back_or_front of t.

val enqueue_front : 'a t -> 'a -> unit

val enqueue_back : 'a t -> 'a -> unit

val clear : 'a t -> unit

clear t removes all elements from t.

val drop : ?n:int -> 'a t -> [ `back | `front ] -> unit

drop ?n t back_or_front drop n elements (default 1) from the back_or_front of t. If t has fewer than n elements then it is cleared.

val drop_front : ?n:int -> 'a t -> unit

val drop_back : ?n:int -> 'a t -> unit

val dequeue : 'a t -> [ `back | `front ] -> 'a option

dequeue t back_or_front remove and return the back_or_front of t

val dequeue_exn : 'a t -> [ `back | `front ] -> 'a

val dequeue_front : 'a t -> 'a option

val dequeue_front_exn : 'a t -> 'a

val dequeue_back : 'a t -> 'a option

val dequeue_back_exn : 'a t -> 'a

val t_of_sexp : (Sexplib.Sexp.t -> 'a) -> Sexplib.Sexp.t -> 'a t

val sexp_of_t : ('a -> Sexplib.Sexp.t) -> 'a t -> Sexplib.Sexp.t

val bin_t : 'a Bin_prot.Type_class.t -> 'a t Bin_prot.Type_class.t

val bin_read_t : 'a Bin_prot.Unsafe_read_c.reader -> 'a t Bin_prot.Read_ml.reader

val bin_read_t_ : 'a Bin_prot.Unsafe_read_c.reader ->
       'a t Bin_prot.Unsafe_read_c.reader

val bin_read_t__ : 'a Bin_prot.Unsafe_read_c.reader ->
       (int -> 'a t) Bin_prot.Unsafe_read_c.reader

val bin_reader_t : 'a Bin_prot.Type_class.reader -> 'a t Bin_prot.Type_class.reader

val bin_size_t : 'a Bin_prot.Size.sizer -> 'a t Bin_prot.Size.sizer

val bin_write_t : 'a Bin_prot.Unsafe_write_c.writer -> 'a t Bin_prot.Write_ml.writer

val bin_write_t_ : 'a Bin_prot.Unsafe_write_c.writer ->
       'a t Bin_prot.Unsafe_write_c.writer

val bin_writer_t : 'a Bin_prot.Type_class.writer -> 'a t Bin_prot.Type_class.writer

create ?initial_length ?never_shrink () create a new t. initial_length is the initial length of the dequeue; it will be able to hold initial_length elements without resizing. It must be positive. If never_shrink is true, the physical array will never shrink; only expand. If initial_length is given without never_shrink then never_shrink is presumed to be true, otherwise never_shrink defaults to false.

front_index t return the index of the front item in t.

front_index_exn t throws an exception if t is empty, otherwise returns the index of the front item in t

back_index t return the index of the back item in t.

back_index_exn t throws an exception if t is empty, otherwise returns the index of the back item in t

get t i return the element at index i. Return None if i is invalid.

get_exn t i return the element at index i. Raise an exception if i is invalid.

peek t back_or_front return the value at the back or front of the dequeue without removing it.

set_exn t i v mutate the element at i.

iter' t ~f iter over the elements of t.

iteri t ~f iter over the elements of t `front_to_back passing in the index.

iteri' t ~f as iter, but also passes in the index of the current element.

fold' t ~init ~f fold over the elements of t

foldi t ~init ~f as fold, but also passes in the index of the current element.

foldi' t ~init ~f as fold', but also passes in the index of the current element to f.

enqueue t back_or_front v push v onto the back_or_front of t.

clear t removes all elements from t.

drop ?n t back_or_front drop n elements (default 1) from the back_or_front of t. If t has fewer than n elements then it is cleared.

dequeue t back_or_front remove and return the back_or_front of t