Module CCFQueue

module CCFQueue: sig .. end

Functional queues



type 'a sequence = ('a -> unit) -> unit 
type 'a klist = unit -> [ `Cons of 'a * 'a klist | `Nil ] 
type 'a equal = 'a -> 'a -> bool 
type 'a printer = Format.formatter -> 'a -> unit 

Basics


type +'a t 
Queue containing elements of type 'a
val empty : 'a t
val is_empty : 'a t -> bool
val singleton : 'a -> 'a t
val doubleton : 'a -> 'a -> 'a t
exception Empty
val cons : 'a -> 'a t -> 'a t
Push element at the front of the queue
val snoc : 'a t -> 'a -> 'a t
Push element at the end of the queue
val take_front : 'a t -> ('a * 'a t) option
Get and remove the first element
val take_front_exn : 'a t -> 'a * 'a t
Same as CCFQueue.take_front, but fails on empty queues.
Raises Empty if the queue is empty
val take_front_l : int -> 'a t -> 'a list * 'a t
take_front_l n q takes at most n elements from the front of q, and returns them wrapped in a list
Raises Invalid_argument if n<0
val take_front_while : ('a -> bool) -> 'a t -> 'a list * 'a t
val take_back : 'a t -> ('a t * 'a) option
Take last element
val take_back_exn : 'a t -> 'a t * 'a
Same as CCFQueue.take_back, but fails on empty queues.
Raises Empty if the queue is empty
val take_back_l : int -> 'a t -> 'a t * 'a list
take_back_l n q removes and returns the last n elements of q. The elements are in the order of the queue, that is, the head of the returned list is the first element to appear via CCFQueue.take_front. take_back_l 2 (of_list [1;2;3;4]) = of_list [1;2], [3;4]
Raises Invalid_argument if n<0
val take_back_while : ('a -> bool) -> 'a t -> 'a t * 'a list

Individual extraction


val first : 'a t -> 'a option
First element of the queue
val last : 'a t -> 'a option
Last element of the queue
val first_exn : 'a t -> 'a
Same as CCFQueue.first but
Raises Empty if the queue is empty
val last_exn : 'a t -> 'a
val nth : int -> 'a t -> 'a option
Return the i-th element of the queue in logarithmic time
val nth_exn : int -> 'a t -> 'a
Unsafe version of CCFQueue.nth
Raises Not_found if the index is wrong
val tail : 'a t -> 'a t
Queue deprived of its first element. Does nothing on empty queues
val init : 'a t -> 'a t
Queue deprived of its last element. Does nothing on empty queues

Global Operations


val append : 'a t -> 'a t -> 'a t
Append two queues. Elements from the second one come after elements of the first one. Linear in the size of the second queue.
val rev : 'a t -> 'a t
Reverse the queue, O(n) complexity
Since 0.10
val map : ('a -> 'b) -> 'a t -> 'b t
Map values
val (>|=) : 'a t -> ('a -> 'b) -> 'b t
Synonym to CCFQueue.map
val size : 'a t -> int
Number of elements in the queue (constant time)
val fold : ('b -> 'a -> 'b) -> 'b -> 'a t -> 'b
val iter : ('a -> unit) -> 'a t -> unit
val equal : 'a equal -> 'a t equal

Conversions


val of_list : 'a list -> 'a t
val to_list : 'a t -> 'a list
val add_seq_front : 'a sequence -> 'a t -> 'a t
val add_seq_back : 'a t -> 'a sequence -> 'a t
val to_seq : 'a t -> 'a sequence
val of_seq : 'a sequence -> 'a t
val to_klist : 'a t -> 'a klist
val of_klist : 'a klist -> 'a t
val (--) : int -> int -> int t
a -- b is the integer range from a to b, both included.
Since 0.10
val (--^) : int -> int -> int t
a -- b is the integer range from a to b, where b is excluded.
Since 0.17
val print : 'a printer -> 'a t printer
Since 0.13