move a bit closer to "the elm architecture"

elm/Stream.elm

@@ -1,7 +1,10 @@
module Stream where
import Date
import Date (Date)
import Html (..)
import Html.Attributes as Attr
import Html.Events (onClick)
import List
import String
import Time
@@ -10,6 +13,14 @@ import Signal
import Post
import Post (Post)
type alias Model =
    { posts         : List Post
    , referenceDate : Date
    }
type Action = NoOp
            | UpdateDate Date
date s = case (Date.fromString s) of
    Ok  d -> d
    Err e -> Date.fromTime 0
@@ -23,9 +34,28 @@ posts = [{title = "Fancy post", content = "Post may have multiple lines now.\nWh
         {title = "Ancient history", content = "Teenage angst!!!!", created = date "2009-06-07T02:54:29"}
        ]
currentDate = Signal.map Date.fromTime <| Time.every Time.minute
-- view
view model = div [] (List.map (Post.view model.referenceDate) (List.sortWith Post.compareByDateReverse model.posts))
-- wiring it all up
initialModel = { posts = posts, referenceDate = date "0" }
view referenceDate =
    div [] (List.map (Post.view referenceDate) (List.sortWith Post.compareByDateReverse posts))
update : Action -> Model -> Model
update action model =
    case action of
      NoOp -> model
      UpdateDate d -> { model | referenceDate <- d }
model : Signal Model
model = Signal.foldp update initialModel <| Signal.merge (Signal.subscribe updates) (Signal.map UpdateDate currentDate)
updates : Signal.Channel Action
updates = Signal.channel NoOp
currentDate : Signal Date
currentDate = Signal.map Date.fromTime <| Time.every Time.minute
main = Signal.map view currentDate
main = Signal.map view model