module BatDeque: sig .. end
Functional double-ended queues
type +'a dq
The type of double-ended queues
type 'a t = 'a dq
A synonym for convenience
include BatEnum.Enumerable
include BatInterfaces.Mappable
val size : 'a dq -> int
size dq is the number of elements in the dq. O(1)
Construction
val empty : 'a dq
The empty deque.
val cons : 'a -> 'a dq -> 'a dq
cons x dq adds x to the front of dq. O(1)
val snoc : 'a dq -> 'a -> 'a dq
snoc x dq adds x to the rear of dq. O(1)
Deconstruction
val front : 'a dq -> ('a * 'a dq) option
front dq returns Some (x, dq') iff x is at the front of
dq and dq' is the rest of dq excluding x, and None if
dq has no elements. O(1) amortized, O(n) worst case
val rear : 'a dq -> ('a dq * 'a) option
rear dq returns Some (dq', x) iff x is at the rear of dq
and dq' is the rest of dq excluding x, and None if dq
has no elements. O(1) amortized, O(n) worst case
Basic operations
val eq : ?eq:('a -> 'a -> bool) -> 'a dq -> 'a dq -> bool
eq dq1 dq2 is true if dq1 and dq2 have the same sequence
of elements. A custom function can be optionally provided with
the eq parameter (default is Pervasives.(=)).
Since 2.2.0
val rev : 'a dq -> 'a dq
rev dq reverses dq. O(1)
val is_empty : 'a dq -> bool
is_empty dq returns false iff dq has no elements. O(1)
val at : ?backwards:bool -> 'a dq -> int -> 'a option
at ~backwards dq k returns the kth element of dq, from
the front if backwards is false, and from the rear if
backwards is true. By default, backwards = false. O(n)
val map : ('a -> 'b) -> 'a dq -> 'b dq
map f dq returns a deque where every element x of dq has
been replaces with f x. O(n)
val mapi : (int -> 'a -> 'b) -> 'a dq -> 'b dq
map f dq returns a deque where every element x of dq has
been replaces with f n x, where n is the position of x
from the front of dq. O(n)
val iter : ('a -> unit) -> 'a dq -> unit
iter f dq calls f x on each element x of dq. O(n)
val iteri : (int -> 'a -> unit) -> 'a dq -> unit
iteri f dq calls f n x on each element x of dq. The first
argument to f is the position of the element from the front of
dq. O(n)
val find : ?backwards:bool -> ('a -> bool) -> 'a dq -> (int * 'a) option
find ~backwards f dq returns Some (n, x) if x at position
n is such that f x is true, or None if there is no such
element. The position n is from the rear if backwards is
true, and from the front if backwards is false. By default,
backwards is false. O(n)
val fold_left : ('acc -> 'a -> 'acc) -> 'acc -> 'a dq -> 'acc
fold_left f acc dq is equivalent to List.fold_left f acc
(to_list dq), but more efficient. O(n)
val fold_right : ('a -> 'acc -> 'acc) -> 'a dq -> 'acc -> 'acc
fold_right f dq acc is equivalent to List.fold_right f
(to_list dq) acc, but more efficient. O(n)
val append : 'a dq -> 'a dq -> 'a dq
append dq1 dq2 represents the concatenateion of dq1 and
dq2. O(min(m, n))
val append_list : 'a dq -> 'a list -> 'a dq
append_list dq l is equivalent to append dq (of_list l), but
more efficient. O(min(m, n))
val prepend_list : 'a list -> 'a dq -> 'a dq
prepent_list l dq is equivalent to append (of_list l) dq,
but more efficient. O(min(m, n))
val rotate_forward : 'a dq -> 'a dq
A cyclic shift of deque elements from rear to front by one position.
As a result, the front element becomes the rear element.
Time: O(1) amortized, O(n) worst-case.
Since 2.3.0
val rotate_backward : 'a dq -> 'a dq
A cyclic shift of deque elements from front to rear by one position.
As a result, the rear element becomes the front element.
Time: O(1) amortized, O(n) worst-case.
Since 2.3.0
val of_list : 'a list -> 'a dq
of_list l is a deque representation of the elements of l.
O(n)
val to_list : 'a dq -> 'a list
to_list dq is a list representation of the elements of dq.
O(n)
val of_enum : 'a BatEnum.t -> 'a dq
of_enum e is a deque representation of the elements of e.
Consumes the enumeration e. O(n)
val enum : 'a dq -> 'a BatEnum.t
enum dq is an enumeration of the elements of dq from the
front to the rear.
This function is O(1), but generating each element of the enumeration
is amortized O(1), and O(n) worst case.
Printing
val print : ?first:string ->
?last:string ->
?sep:string -> ('a, 'b) BatIO.printer -> ('a dq, 'b) BatIO.printer
Print the contents of the deque. O(n)