package containers

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package containers
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complements to list

include module type of Stdlib.ListLabels
val length : 'a list -> int
val hd : 'a list -> 'a
val compare_lengths : 'a list -> 'b list -> int
val compare_length_with : 'a list -> len:int -> int
val tl : 'a list -> 'a list
val nth : 'a list -> int -> 'a
val nth_opt : 'a list -> int -> 'a option
val rev : 'a list -> 'a list
val rev_append : 'a list -> 'a list -> 'a list
val concat : 'a list list -> 'a list
val iter : f:('a -> unit) -> 'a list -> unit
val rev_map : f:('a -> 'b) -> 'a list -> 'b list
val fold_left : f:('a -> 'b -> 'a) -> init:'a -> 'b list -> 'a
val iter2 : f:('a -> 'b -> unit) -> 'a list -> 'b list -> unit
val map2 : f:('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list
val rev_map2 : f:('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list
val fold_left2 : f:('a -> 'b -> 'c -> 'a) -> init:'a -> 'b list -> 'c list -> 'a
val fold_right2 : f:('a -> 'b -> 'c -> 'c) -> 'a list -> 'b list -> init:'c -> 'c
val for_all : f:('a -> bool) -> 'a list -> bool
val exists : f:('a -> bool) -> 'a list -> bool
val for_all2 : f:('a -> 'b -> bool) -> 'a list -> 'b list -> bool
val exists2 : f:('a -> 'b -> bool) -> 'a list -> 'b list -> bool
val memq : 'a -> set:'a list -> bool
val find : f:('a -> bool) -> 'a list -> 'a
val find_opt : f:('a -> bool) -> 'a list -> 'a option
val find_all : f:('a -> bool) -> 'a list -> 'a list
val partition : f:('a -> bool) -> 'a list -> 'a list * 'a list
val assoc : 'a -> ('a * 'b) list -> 'b
val assoc_opt : 'a -> ('a * 'b) list -> 'b option
val assq : 'a -> ('a * 'b) list -> 'b
val assq_opt : 'a -> ('a * 'b) list -> 'b option
val mem_assoc : 'a -> map:('a * 'b) list -> bool
val mem_assq : 'a -> map:('a * 'b) list -> bool
val remove_assoc : 'a -> ('a * 'b) list -> ('a * 'b) list
val remove_assq : 'a -> ('a * 'b) list -> ('a * 'b) list
val split : ('a * 'b) list -> 'a list * 'b list
val combine : 'a list -> 'b list -> ('a * 'b) list
val sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list
val stable_sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list
val fast_sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list
val merge : cmp:('a -> 'a -> int) -> 'a list -> 'a list -> 'a list
type 'a t = 'a list
val empty : 'a t
val is_empty : _ t -> bool

is_empty l returns true iff l = []

  • since 0.11
val map : f:('a -> 'b) -> 'a t -> 'b t

Safe version of map

val (>|=) : 'a t -> ('a -> 'b) -> 'b t

Infix version of map with reversed arguments

  • since 0.5
val cons : 'a -> 'a t -> 'a t

cons x l is x::l

  • since 0.12
val append : 'a t -> 'a t -> 'a t

Safe version of append

val cons_maybe : 'a option -> 'a t -> 'a t

cons_maybe (Some x) l is x :: l cons_maybe None l is l

  • since 0.13
val (@) : 'a t -> 'a t -> 'a t
val filter : f:('a -> bool) -> 'a t -> 'a t

Safe version of List.filter

val fold_right : ('a -> 'b -> 'b) -> 'a t -> 'b -> 'b

Safe version of fold_right

val fold_while : f:('a -> 'b -> 'a * [ `Stop | `Continue ]) -> init:'a -> 'b t -> 'a

Fold until a stop condition via ('a, `Stop) is indicated by the accumulator

  • since 0.8
val fold_map : f:('acc -> 'a -> 'acc * 'b) -> init:'acc -> 'a list -> 'acc * 'b list

fold_map f acc l is a fold_left-like function, but it also maps the list to another list.

  • since 0.14
val fold_map2 : f:('acc -> 'a -> 'b -> 'acc * 'c) -> init:'acc -> 'a list -> 'b list -> 'acc * 'c list

fold_map2 is to fold_map what List.map2 is to List.map.

  • raises Invalid_argument

    if the lists do not have the same length

  • since 0.16
val fold_filter_map : f:('acc -> 'a -> 'acc * 'b option) -> init:'acc -> 'a list -> 'acc * 'b list

fold_filter_map f acc l is a fold_left-like function, but also generates a list of output in a way similar to filter_map

  • since 0.17
val fold_flat_map : f:('acc -> 'a -> 'acc * 'b list) -> init:'acc -> 'a list -> 'acc * 'b list

fold_flat_map f acc l is a fold_left-like function, but it also maps the list to a list of lists that is then flatten'd..

  • since 0.14
val init : int -> f:(int -> 'a) -> 'a t

Similar to Array.init

  • since 0.6
val compare : ('a -> 'a -> int) -> 'a t -> 'a t -> int
val equal : ('a -> 'a -> bool) -> 'a t -> 'a t -> bool
val flat_map : f:('a -> 'b t) -> 'a t -> 'b t

Map and flatten at the same time (safe). Evaluation order is not guaranteed.

val flatten : 'a t t -> 'a t

Safe flatten

val product : f:('a -> 'b -> 'c) -> 'a t -> 'b t -> 'c t

Cartesian product of the two lists, with the given combinator

val fold_product : f:('c -> 'a -> 'b -> 'c) -> init:'c -> 'a t -> 'b t -> 'c

Fold on the cartesian product

val diagonal : 'a t -> ('a * 'a) t

All pairs of distinct positions of the list. list_diagonal l will return the list of List.nth i l, List.nth j l if i < j.

val partition_map : f:('a -> [< `Left of 'b | `Right of 'c | `Drop ]) -> 'a list -> 'b list * 'c list

partition_map f l maps f on l and gather results in lists:

  • if f x = `Left y, adds y to the first list
  • if f x = `Right z, adds z to the second list
  • if f x = `Drop, ignores x
  • since 0.11
val pure : 'a -> 'a t
val (<*>) : ('a -> 'b) t -> 'a t -> 'b t
val (<$>) : ('a -> 'b) -> 'a t -> 'b t
val return : 'a -> 'a t
val (>>=) : 'a t -> ('a -> 'b t) -> 'b t
val take : int -> 'a t -> 'a t

Take the n first elements, drop the rest

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

Drop the n first elements, keep the rest

val hd_tl : 'a t -> 'a * 'a t

hd_tl (x :: l) returns hd, l.

  • raises Failure

    if the list is empty

  • since 0.16
val take_drop : int -> 'a t -> 'a t * 'a t

take_drop n l returns l1, l2 such that l1 @ l2 = l and length l1 = min (length l) n

val take_while : f:('a -> bool) -> 'a t -> 'a t
  • since 0.13
val drop_while : f:('a -> bool) -> 'a t -> 'a t
  • since 0.13
val last : int -> 'a t -> 'a t

last n l takes the last n elements of l (or less if l doesn't have that many elements

val head_opt : 'a t -> 'a option

First element.

  • since 0.20
val last_opt : 'a t -> 'a option

Last element.

  • since 0.20
val find_pred : f:('a -> bool) -> 'a t -> 'a option

find_pred p l finds the first element of l that satisfies p, or returns None if no element satisfies p

  • since 0.11
val find_pred_exn : f:('a -> bool) -> 'a t -> 'a

Unsafe version of find_pred

  • raises Not_found

    if no such element is found

  • since 0.11
val find_map : f:('a -> 'b option) -> 'a t -> 'b option

find_map f l traverses l, applying f to each element. If for some element x, f x = Some y, then Some y is returned. Otherwise the call returns None

  • since 0.11
val find_mapi : f:(int -> 'a -> 'b option) -> 'a t -> 'b option

Like find_map, but also pass the index to the predicate function.

  • since 0.11
val find_idx : f:('a -> bool) -> 'a t -> (int * 'a) option

find_idx p x returns Some (i,x) where x is the i-th element of l, and p x holds. Otherwise returns None

val remove : ?eq:('a -> 'a -> bool) -> key:'a -> 'a t -> 'a t

remove ~key l removes every instance of key from l. Tailrec.

  • parameter eq

    equality function

  • since 0.11
val filter_map : f:('a -> 'b option) -> 'a t -> 'b t

Map and remove elements at the same time

val sorted_merge : ?cmp:('a -> 'a -> int) -> 'a list -> 'a list -> 'a list

Merges elements from both sorted list

val sort_uniq : ?cmp:('a -> 'a -> int) -> 'a list -> 'a list

Sort the list and remove duplicate elements

val sorted_merge_uniq : ?cmp:('a -> 'a -> int) -> 'a list -> 'a list -> 'a list

sorted_merge_uniq l1 l2 merges the sorted lists l1 and l2 and removes duplicates

  • since 0.10
val is_sorted : ?cmp:('a -> 'a -> int) -> 'a list -> bool

is_sorted l returns true iff l is sorted (according to given order)

  • parameter cmp

    the comparison function (default Pervasives.compare)

  • since 0.17
val sorted_insert : ?cmp:('a -> 'a -> int) -> ?uniq:bool -> 'a -> 'a list -> 'a list

sorted_insert x l inserts x into l such that, if l was sorted, then sorted_insert x l is sorted too.

  • parameter uniq

    if true and x is already in sorted position in l, then x is not duplicated. Default false (x will be inserted in any case).

  • since 0.17
val uniq_succ : ?eq:('a -> 'a -> bool) -> 'a list -> 'a list

uniq_succ l removes duplicate elements that occur one next to the other. Examples: uniq_succ [1;2;1] = [1;2;1] uniq_succ [1;1;2] = [1;2]

  • since 0.10
val group_succ : ?eq:('a -> 'a -> bool) -> 'a list -> 'a list list

group_succ ~eq l groups together consecutive elements that are equal according to eq

  • since 0.11

Indices

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

Fold on list, with index

val get_at_idx : int -> 'a t -> 'a option
val get_at_idx_exn : int -> 'a t -> 'a

Get the i-th element, or

  • raises Not_found

    if the index is invalid

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

Set i-th element (removes the old one), or does nothing if index is too high

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

Insert at i-th position, between the two existing elements. If the index is too high, append at the end of the list

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

Remove element at given index. Does nothing if the index is too high.

Set Operators

Those operations maintain the invariant that the list does not contain duplicates (if it already satisfies it)

val add_nodup : ?eq:('a -> 'a -> bool) -> 'a -> 'a t -> 'a t

add_nodup x set adds x to set if it was not already present. Linear time.

  • since 0.11
val remove_one : ?eq:('a -> 'a -> bool) -> 'a -> 'a t -> 'a t

remove_one x set removes one occurrence of x from set. Linear time.

  • since 0.11
val mem : ?eq:('a -> 'a -> bool) -> 'a -> 'a t -> bool

Membership to the list. Linear time

val subset : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t -> bool

Test for inclusion

val uniq : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t

Remove duplicates w.r.t the equality predicate. Complexity is quadratic in the length of the list, but the order of elements is preserved. If you wish for a faster de-duplication but do not care about the order, use sort_uniq

val union : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t -> 'a t

List union. Complexity is product of length of inputs.

val inter : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t -> 'a t

List intersection. Complexity is product of length of inputs.

Other Constructors

val range_by : step:int -> int -> int -> int t

range_by ~step i j iterates on integers from i to j included, where the difference between successive elements is step. use a negative step for a decreasing list.

  • raises Invalid_argument

    if step=0

  • since 0.18
val range : int -> int -> int t

range i j iterates on integers from i to j included . It works both for decreasing and increasing ranges

val range' : int -> int -> int t

Same as range but the second bound is excluded. For instance range' 0 5 = [0;1;2;3;4]

val (--) : int -> int -> int t

Infix alias for range

val (--^) : int -> int -> int t

Infix alias for range'

  • since 0.17
val replicate : int -> 'a -> 'a t

Replicate the given element n times

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

Concatenate the list with itself n times

Association Lists

module Assoc : sig ... end

References on Lists

  • since 0.3.3
module Ref : sig ... end
module type MONAD = sig ... end
module Traverse (M : MONAD) : sig ... end

Conversions

type 'a sequence = ('a -> unit) -> unit
type 'a gen = unit -> 'a option
type 'a klist = unit -> [ `Nil | `Cons of 'a * 'a klist ]
type 'a printer = Stdlib.Format.formatter -> 'a -> unit
type 'a random_gen = Stdlib.Random.State.t -> 'a
val random : 'a random_gen -> 'a t random_gen
val random_non_empty : 'a random_gen -> 'a t random_gen
val random_len : int -> 'a random_gen -> 'a t random_gen
val random_choose : 'a t -> 'a random_gen

Randomly choose an element in the list.

  • raises Not_found

    if the list is empty

val random_sequence : 'a random_gen t -> 'a t random_gen
val to_seq : 'a t -> 'a sequence
val of_seq : 'a sequence -> 'a t
val to_gen : 'a t -> 'a gen
val of_gen : 'a gen -> 'a t
val to_klist : 'a t -> 'a klist
val of_klist : 'a klist -> 'a t

Infix Operators

It is convenient to openCCList.Infix to access the infix operators without cluttering the scope too much.

  • since 0.16
module Infix : sig ... end

IO

val pp : ?start:string -> ?stop:string -> ?sep:string -> 'a printer -> 'a t printer
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