coffeescript-business.elm

main = document.getElementById 'main'
app  = Elm.embed Elm.Main, main

backEnd = (msg) ->
  # ...

{submitEmail, updateEmail} = app.ports

email = "ye"

submitEmail.subscribe (what) ->
  console.log 'Submit Email!', what, email
  backEnd email: email

updateEmail.subscribe (what) ->
  console.log 'Update Email!', what
  email = what

elm-business.elm

-- ..

email : String -> Address Action -> Html
email content address =
  div 
    [ style 
        [ ("margin",  "auto")
        , ("width",   "60%")
        ]
    ] 
    [ input 
        [ class       "field"
        , placeholder "enter your email here"
        , value       content
        , on "input"  targetValue 
          <| message inputString.address
          --<| (\string -> Signal.message address (EmailField string))
        ] 
        []
    , button 
        [ style 
            [ ("background-color", "#030907")
            , ("border",           "none"   )
            , ("outline",          "none"   )
            ]
        , class  "point link"
        , on "click" targetValue 
          <| message subscribePress.address
        ] 
        [ text   "subscribe"  ]
    ]

port submitEmail : Signal String
port submitEmail = 
  Signal.map (\str -> str) subscribePress.signal

port updateEmail : Signal String
port updateEmail =
  Signal.map (\str -> str) inputString.signal

inputString : Mailbox String
inputString = mailbox "these strings dont matter"

subscribePress : Mailbox String
subscribePress = mailbox "hell ye mf"

- ..