package travesty

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in-package search v0.2.0

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Parameters
Signature

Traversable containers, monad extensions, and more

Install

dune-project

Dependency

mattwindsor91.github.io Readme Changelog Edit opam file Versions (8)

Authors

M

Matt Windsor <mattwindsor91@gmail.com>

Maintainers

M

Matt Windsor <mattwindsor91@gmail.com>

Sources

travesty-0.7.2.tbz

sha256=49d43ea0e9cef32d493fcc1561fc7480c55d9a2490700e487f4d5c3aff562d61

sha512=1cd77071adfb4583d0fcd27469b97bc64b7278761949aaaf415768aec14f6a1243e14575155c75033a5141a0320b4f56687381dc2bc56432a5ea63ea8613d968

doc/travesty.containers/Travesty_containers/Singleton/On_monad/index.html

Module `Singleton.On_monad`

On_monad implements applicative folding and mapping operators for a given monad M, including arity-1 specific operators.

Parameters

module M : Base.Monad.S

Signature

include Travesty.Traversable_types.Generic_on_monad
  with type 'a t := 'a t
   and type 'a elt := 'a
  with module M := M

All applicative operators are available through lowering the monad to an applicative functor.

include Travesty.Traversable_types.Generic_on_applicative
  with module M := Travesty.Monad_exts.App(M)
  with type 'a t := 'a t
  with type 'a elt := 'a

include Travesty.Traversable_types.Basic_generic_on_applicative
  with module M := Travesty.Monad_exts.App(M)
  with type 'a t := 'a t
  with type 'a elt := 'a

Generic refers to the container type as 'a t, and the element type as 'a elt; substitute t/elt (arity-0) or 'a t/'a (arity-1) accordingly below.

include Travesty.Generic_types.Generic
  with type 'a t := 'a t
  with type 'a elt := 'a

Source

val map_m : 
  'a t ->
  f:('a -> 'b Travesty.Monad_exts.App(M).t) ->
  'b t Travesty.Monad_exts.App(M).t

map_m c ~f maps f over every t in c, threading through an applicative functor.

Example:

  (* Travesty_base_exts.List adds applicative traversals to a list;
     With_errors (in S1_container) implements them on the On_error
     applicative functor. *)

  let f x =
    Or_error.(if 0 < x then error_string "negative!" else ok x)
  in
  List.With_errors.map_m integers ~f

Source

val fold_map_m : 
  'a t ->
  f:('acc -> 'a -> ('acc * 'b) M.t) ->
  init:'acc ->
  ('acc * 'b t) M.t

fold_map_m c ~f ~init folds f applicatively over every t in c, threading through an accumulator with initial value init.

Sourceval fold_m : 'a t -> init:'acc -> f:('acc -> 'a -> 'acc M.t) -> 'acc M.t

fold_m x ~init ~f folds the applicative computation f over x, starting with initial value init, and returning the final value inside the applicative effect.

Sourceval iter_m : 'a t -> f:('a -> Base.unit M.t) -> Base.unit M.t

iter_m x ~f iterates the computation f over x, returning the final applicative effect.

Sourceval mapi_m : f:(Base.int -> 'a -> 'b M.t) -> 'a t -> 'b t M.t

mapi_m ~f x behaves as map_m, but also supplies f with the index of the element. This index should match the actual position of the element in the container x.

Sourceval sequence_m : 'a M.t t -> 'a t M.t

sequence_m x lifts a container of applicatives x to an applicative containing a container, by sequencing the applicative effects from left to right.