elm-architecture-tutorial/src/Main.elm at master · evancz/elm-architecture-tutorial · GitHub

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module Main exposing (main)

import Browser
import Html exposing (Html, button, div, text)
import Html.Events exposing (onClick)


-- MAIN


main =
  Browser.sandbox { init = init, update = update, view = view }


-- MODEL


type alias Model = Int


init : Model
init =
  0


-- UPDATE


type Msg
  = Increment
  | Decrement


update : Msg -> Model -> Model
update msg model =
  case msg of
    Increment ->
      model + 1

    Decrement ->
      model - 1


-- VIEW


view : Model -> Html Msg
view model =
  div []
    [ button [ onClick Decrement ] [ text "-" ]
    , div [] [ text (String.fromInt model) ]
    , button [ onClick Increment ] [ text "+" ]
    ]