const numbers = [1, 2, 3, 4, 5];
let squares = [];

for (const i = 0, length = numbers.length; i < length; i++) {
    squares.push(numbers[i] * numbers[i]);
}

main : Program Never Model Msg
main =
    program { view = view, init = init, update = update, subscriptions = subscriptions }

-- ...


subscriptions : Model -> Sub Msg
subscriptions model =
    usernameFromLS ReceivedUsernameFromLS

port registerUsernameToLS : String -> Cmd msg

port usernameFromLS : (String -> msg) -> Sub msg

const app = Elm.Main.embed(root);

app.ports.registerUsernameToLS.subscribe(username => {
    window.localStorage.setItem('username', username)
});

if (window.localStorage.getItem('username') !== null) {
    const username = window.localStorage.getItem('username');
    app.ports.usernameFromLS.send(username);
}

module Tests exposing (..)

import Test exposing (..)
import Expect
import App exposing (update, Msg(CoinFlipped), CoinState(Heads))


all : Test
all =
    describe "A CoinFlipped should start a new game"
        [ test  <|
            \() ->
                Expect.equal (update (CoinFlipped Heads) NoGame) (Game Heads)
        ]