module Main exposing (main) import Browser import Html exposing (Html, button, div, text) import Html.Events exposing (onClick) type alias Model = { count : Int } initialModel : Model initialModel = { count = 0 } type Msg = Increment | Decrement update : Msg -> Model -> Model update msg model = case msg of Increment -> { model | count = model.count + 1 } Decrement -> { model | count = model.count - 1 } view : Model -> Html Msg view model = div [] [ button [ onClick Increment ] [ text "+1" ] , div [] [ text <| String.fromInt model.count ] , button [ onClick Decrement ] [ text "-1" ] ] main : Program () Model Msg main = Browser.sandbox { init = initialModel , view = view , update = update }