elm app template

template.elm

port module Main exposing (..)

import Html.App as Html
import Html exposing (..)
import Html.Events exposing (..)
import Html.Attributes exposing (..)
import Json.Decode as Json
import Debug exposing (..)

main : Program Never
main =
  Html.program
    { init = { value = 0 } ! []
    , view = view
    , update = update
    , subscriptions = subscriptions
    }

-- MODEL
type alias Model = { value : Int }

-- VIEW
view : Model -> Html Msg
view model =
  let
    onNumInput : Json.Decoder Msg
    onNumInput =
      Json.map UpdateNum <|
        Json.at ["target", "valueAsNumber"] Json.int
  in input
       [ type' "number"
       , on "change" onNumInput
       , value (toString model.value)
       ]
       []

-- UPDATE
type Msg = UpdateNum Int

update : Msg -> Model -> (Model, Cmd Msg)
update msg model =
  case msg of
    UpdateNum newval ->
      (log "model" { model | value = newval }) ! []

-- SUBSCRIPTIONS

subscriptions : Model -> Sub Msg
subscriptions model =
  externalfeed UpdateNum

port externalfeed : (Int -> msg) -> Sub msg

template_simple.elm

module Main exposing (..)

import Html.App as Html
import Html exposing (..)
import Html.Events exposing (..)
import Html.Attributes exposing (..)
import Json.Decode as Json
import Debug exposing (..)

main : Program Never
main =
  Html.beginnerProgram
    { model = { value = 0 }
    , view = view
    , update = update
    }

-- MODEL
type alias Model = { value : Int }

-- VIEW
view : Model -> Html Msg
view model =
  let
    onNumInput : Json.Decoder Msg
    onNumInput =
      Json.map UpdateNum <|
        Json.at ["target", "valueAsNumber"] Json.int
  in input
       [ type' "number"
       , on "change" onNumInput
       , value (toString model.value)
       ]
       []

-- UPDATE
type Msg = UpdateNum Int

update : Msg -> Model -> Model
update msg model =
  case msg of
    UpdateNum newval ->
      log "model" { model | value = newval }