Sendable Data for Elm

SendableData.elm

module SendableData exposing (..)

import Http

type SendableData e r wrapped
  = NotSent wrapped
  | Sending wrapped
  | FailedSending e wrapped
  | Sent r wrapped

type alias SendableWebData r wrapped
  = SendableData Http.Error r wrapped

map : (wrapped -> wrapped_) -> SendableData e r wrapped -> SendableData e r wrapped_
map f data =
  case data of
    NotSent value ->
      NotSent (f value)

    Sending value ->
      Sending (f value)

    FailedSending e value ->
      FailedSending e (f value)

    Sent r value ->
      Sent r (f value)

unwrap : SendableData e r wrapped -> wrapped
unwrap data =
  case data of
    NotSent value ->
      value

    Sending value ->
      value

    FailedSending e value ->
      value

    Sent r value ->
      value

replace : SendableData e r wrapped -> wrapped_ -> SendableData e r wrapped_
replace orig newData =
  case orig of
    NotSent _ ->
      NotSent newData

    Sending _ ->
      Sending newData

    FailedSending error _ ->
      FailedSending error newData

    Sent resp _ ->
      Sent resp newData

get : (wrapped -> b) -> SendableData e r wrapped -> b
get f data =
  f (unwrap data)

fromResult : wrapped -> Result e r -> SendableData e r wrapped
fromResult wrapped result =
  case result of
    Err err ->
      FailedSending err wrapped

    Ok ok ->
      Sent ok wrapped