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

main : Program Never
main = Html.beginnerProgram { model = model
                            , view = view
                            , update = update
                            }

type alias Model = Int
model : Model
model = 0

type Msg = Increment | Decrement

update : Msg -> Model -> Model
update msg model = case msg of
                       Increment -> model + 1
                       Decrement -> model - 1
view : Model -> Html Msg
view model = div []
             [ button [ onClick Decrement ] [text "-"]
             , div [] [text (toString model)]
             , button [ onClick Increment ] [text "+"]
             ]