NoRedInk/rocket-update

A simpler alternative to (!)

rocket-update 🚀

This package provides a simpler alternative to the (!) operator.

Tuple Rocketry

The "rocket operator" (=>) does nothing more than return a tuple:

("display" => "none") == ( "display", "none" )

Style Rocketry

It looks kinda nice to use this for things like styles:

button [ style [ "display" => "none" ] ] [ text "invisible!" ]

instead of

button [ style [ ( "display", "none" ) ] ] [ text "invisible!" ]

Update Rocketry

If you tweak update to return ( model, List (Cmd msg) ), then you can use (=>) to serve the same purpose as (!), like so:

update : Msg -> Model -> ( Model, List (Cmd Msg) )
update msg model =
    case msg of
        Reset ->
            { model | stuff = newStuff } => []

        SendRequest ->
            model => [ Http.send someRequest ]

        SendOtherRequest ->
            model
                |> doSomethingToModel
                |> doSomethingElseToModel
                => [ Http.send someOtherRequest ]

To get an update function of this type, just use the Rocket.batchUpdate function when calling program and you're all set. (There's a batchInit function for init too, so update and init can be consistent.)

main : Program Never Model Msg
main =
    Html.program
        { init = init >> Rocket.batchInit
        , update = update >> Rocket.batchUpdate
        , view = view
        , subscriptions = subscriptions
        }

That's it!

In the example/ folder you can find elm-todomvc revised to use this style.

Enjoy! 🚀