Elm defaultValue vs value -- Paste into http://elm-lang.org/try

.elm

import Html exposing (..)
import Html.Attributes exposing (..)
import Html.Events exposing (onInput, onClick)


main =
  Html.beginnerProgram { model = Model "" "", view = view, update = update }


type alias Model =
    { defaultValueEg : String
    , valueEg : String
    }


view model =
  div []
    [ h1 [] [ text "Using defaultValue" ]
    , textarea [ onInput Text1Input, defaultValue model.defaultValueEg ] []
    , button [ onClick ResetText1 ] [ text "Reset" ]
    , h1 [] [ text "Using value" ]
    , textarea [ onInput Text2Input, value model.valueEg ] []
    , button [ onClick ResetText2 ] [ text "Reset" ]
    , div [] [ text (toString model) ]
    ]


type Msg
  = Text1Input String
  | ResetText1
  | Text2Input String
  | ResetText2


update msg model =
  case msg of
    Text1Input str ->
      { model | defaultValueEg = str }

    ResetText1 ->
      { model | defaultValueEg = "" }

    Text2Input str ->
      { model | valueEg = str }

    ResetText2 ->
      { model | valueEg = "" }