bwd 2.3.0 · OCaml Package

This module is similar to ListLabels but for backward lists.

Notes on the discrepancies with ListLabels:

New:
- prepend was added as the forward version of append.
- to_list and of_list were added for conversions between standard lists.
- Infix was added for the infix notation.
Changed:
- cons was replaced by snoc.
- append was replaced by a new version that performs the "textual order yoga".
- All indices count from the right rather than the left: nth, nth_opt, init, iteri, mapi, and filteri.
- All iteration functions work from the right rather than the left: iter, map, fold_left, fold_right, exists, mem, find, filter, and other similar functions.
Forbidden:
- Functions rev, rev_append, rev_map, and rev_map2 will never be included.
Missing but may be added in the future:
- tl (as hd for lists), hd (as tl for lists), concat, flatten, concat_map.
- Functions related to association lists.
- Functions related to sorting.
- Conversion from/to sequences.

Please open a GitHub issue if you want a function to be included. We want to make this library useful to you, too!

type 'a t = 'a bwd =

| Emp
| Snoc of 'a bwd * 'a

val length : 'a bwd -> int

val compare_lengths : 'a bwd -> 'a bwd -> int

val compare_length_with : 'a bwd -> len:int -> int

val is_empty : 'a bwd -> bool

val snoc : 'a bwd -> 'a -> 'a bwd

val nth : 'a bwd -> int -> 'a

val nth_opt : 'a bwd -> int -> 'a option

val init : len:int -> f:(int -> 'a) -> 'a bwd

val append : 'a bwd -> 'a list -> 'a bwd

val prepend : 'a bwd -> 'a list -> 'a list

Comparison

val equal : eq:('a -> 'a -> bool) -> 'a bwd -> 'a bwd -> bool

val compare : cmp:('a -> 'a -> int) -> 'a bwd -> 'a bwd -> int

Iterators

Note that the iteration direction is from the right to the left, in the opposite direction of the corresponding functions in ListLabels.

val iter : f:('a -> unit) -> 'a bwd -> unit

val iteri : f:(int -> 'a -> unit) -> 'a bwd -> unit

val map : f:('a -> 'b) -> 'a bwd -> 'b bwd

val mapi : f:(int -> 'a -> 'b) -> 'a bwd -> 'b bwd

val filter_map : f:('a -> 'b option) -> 'a bwd -> 'b bwd

val fold_left : f:('a -> 'b -> 'a) -> init:'a -> 'b bwd -> 'a

val fold_right_map : 
  f:('a -> 'b -> 'b * 'c) ->
  'a bwd ->
  init:'b ->
  'b * 'c bwd

val fold_right : f:('a -> 'b -> 'b) -> 'a bwd -> init:'b -> 'b

Iterators on two lists

Note that the iteration direction is from the right to the left, in the opposite direction of the corresponding functions in ListLabels.

val iter2 : f:('a -> 'b -> unit) -> 'a bwd -> 'b bwd -> unit

val map2 : f:('a -> 'b -> 'c) -> 'a bwd -> 'b bwd -> 'c bwd

val fold_left2 : f:('a -> 'b -> 'c -> 'a) -> init:'a -> 'b bwd -> 'c bwd -> 'a

val fold_right2 : f:('a -> 'b -> 'c -> 'c) -> 'a bwd -> 'b bwd -> init:'c -> 'c

List scanning

Note that the iteration direction is from the right to the left, in the opposite direction of the corresponding functions in ListLabels.

val for_all : f:('a -> bool) -> 'a bwd -> bool

val exists : f:('a -> bool) -> 'a bwd -> bool

val for_all2 : f:('a -> 'b -> bool) -> 'a bwd -> 'b bwd -> bool

val exists2 : f:('a -> 'b -> bool) -> 'a bwd -> 'b bwd -> bool

val mem : 'a -> set:'a bwd -> bool

val memq : 'a -> set:'a bwd -> bool

List searching

Note that the iteration direction is from the right to the left, in the opposite direction of the corresponding functions in ListLabels.

val find : f:('a -> bool) -> 'a bwd -> 'a

val find_opt : f:('a -> bool) -> 'a bwd -> 'a option

val find_index : f:('a -> bool) -> 'a bwd -> int option

val find_map : f:('a -> 'b option) -> 'a bwd -> 'b option

val find_mapi : f:(int -> 'a -> 'b option) -> 'a bwd -> 'b option

val filter : f:('a -> bool) -> 'a bwd -> 'a bwd

val find_all : f:('a -> bool) -> 'a bwd -> 'a bwd

val filteri : f:(int -> 'a -> bool) -> 'a bwd -> 'a bwd

val partition : f:('a -> bool) -> 'a bwd -> 'a bwd * 'a bwd

val partition_map : f:('a -> ('b, 'c) Either.t) -> 'a bwd -> 'b bwd * 'c bwd

Lists of pairs

val split : ('a * 'b) bwd -> 'a bwd * 'b bwd

val combine : 'a bwd -> 'b bwd -> ('a * 'b) bwd

Backward and forward lists

val to_list : 'a bwd -> 'a list

val of_list : 'a list -> 'a bwd

Infix notation

module Infix : sig ... end

package bwd

Comparison

Iterators

Iterators on two lists

List scanning

List searching

Lists of pairs

Backward and forward lists

Infix notation