Alist (p.travesty.0.7.2.doc.travesty.base_exts.Travesty_base

Sourcetype ('k, 'v) t = ('k, 'v) Base.List.Assoc.t

Defined to let this module be used directly in chaining operations etc.

Associative lists are bi-traversable (and therefore bi-mappable); the left type is keys, and the right type is values.

Here is an example of bi-mapping:

  bi_map
    [("foo", 27); ("bar", 53); ("baz", 99)]
    ~left:String.capitalize ~right:Int.neg

  (* returns: [("Foo", -27); ("Bar", -53); ("Baz", -99)] *)

include Travesty.Bi_traversable_types.S2 with type ('l, 'r) t := ('l, 'r) t

include Base.T2 with type ('l, 'r) t := ('l, 'r) t

include Travesty.Bi_traversable_types.Generic
  with type ('l, 'r) t := ('l, 'r) t
   and type 'l left := 'l
   and type 'r right := 'r

include Travesty.Generic_types.Bi_generic
  with type ('l, 'r) t := ('l, 'r) t
  with type 'l left := 'l
  with type 'r right := 'r

We can do non-monadic bi-mapping operations.

include Travesty.Bi_mappable_types.Generic
  with type ('l, 'r) t := ('l, 'r) t
   and type 'l left := 'l
   and type 'r right := 'r

include Travesty.Bi_mappable_types.Basic_generic
  with type ('l, 'r) t := ('l, 'r) t
  with type 'l left := 'l
  with type 'r right := 'r

include Travesty.Generic_types.Bi_generic
  with type ('l, 'r) t := ('l, 'r) t
  with type 'l left := 'l
  with type 'r right := 'r

Source

val bi_map : 
  ('l1, 'r1) t ->
  left:('l1 -> 'l2) ->
  right:('r1 -> 'r2) ->
  ('l2, 'r2) t

bi_map c ~left ~right maps left over every 'l1 left, and right over every 'r1 right, in c.

Sourceval map_left : ('l1, 'r) t -> f:('l1 -> 'l2) -> ('l2, 'r) t

map_left c ~f maps f over the left type of c only.

Sourceval map_right : ('l, 'r1) t -> f:('r1 -> 'r2) -> ('l, 'r2) t

map_right c ~f maps f over the right type of c only.

module On
  (M : Base.Applicative.S) : 
  Travesty.Bi_traversable_types.Generic_on_applicative
    with type ('l, 'r) t := ('l, 'r) t
     and type 'l left := 'l
     and type 'r right := 'r
     and module M := M

On implements bi-traversal operators for a given applicative functor M.

module On_monad
  (M : Base.Monad.S) : 
  Travesty.Bi_traversable_types.Generic_on_applicative
    with type ('l, 'r) t := ('l, 'r) t
     and type 'l left := 'l
     and type 'r right := 'r
     and module M := Travesty.Monad_exts.App(M)

On_monad implements bi-traversal operators for a given monad M.

module With_errors : 
  Travesty.Bi_traversable_types.Generic_on_applicative
    with type ('l, 'r) t := ('l, 'r) t
     and type 'l left := 'l
     and type 'r right := 'r
     and module M := Base.Or_error

With_errors specialises On_monad to the error_monad.

Source

val compose : 
  ('a, 'b) t ->
  ('b, 'c) t ->
  equal:('b -> 'b -> bool) ->
  ('a, 'c) t

compose a b ~equal produces an associative list that returns (x, z) for each (x, y) in a such that a (y', z) exists in b, and equal y y' is true.