Draft component model.

src/Material/Component.elm

@@ -0,0 +1,126 @@
+module Material.Component where
+
+import Effects exposing (Effects)
+import Html exposing (Html)
+import Dict exposing (Dict)
+
+import Material.Button as Button
+import Material.Style exposing (Style)
+import Material.Textfield as Textfield
+
+type Action model = 
+  A (model -> (model, Effects (Action model)))
+  
+type alias Updater model action = 
+  action -> model -> (model, Effects action)
+
+
+update : Updater State (Action State)
+update (A f) model = 
+  f model
+
+
+
+map1st : (a -> c) -> (a,b) -> (c,b)
+map1st f (x,y) = (f x, y)
+
+
+map2nd : (b -> c) -> (a,b) -> (a,c)
+map2nd f (x,y) = (x, f y)
+
+
+pack : Updater model action -> action -> Action model
+pack update action = 
+  A ( \m -> map2nd (Effects.map (pack update)) (update action m) )
+
+
+type alias View model action a = 
+  Signal.Address action -> model -> a
+
+
+type alias Component model action a = 
+  { view : View model action a
+  , update : Updater model action 
+  }
+
+
+type alias States a = 
+  Dict Int a 
+
+
+type alias State =
+  { button : States Button.Model
+  , textfield : States Textfield.Model
+  }
+
+
+state0 : State
+state0 = 
+  { button = Dict.empty
+  , textfield = Dict.empty
+  }
+
+
+buttonComponent : Component Button.Model Button.Action (List Style -> List Html -> Html)
+buttonComponent = 
+  { view = Button.raised
+  , update = Button.update
+  }
+
+textfieldComponent : Component Textfield.Model Textfield.Action Html
+textfieldComponent = 
+  { view = Textfield.view
+  , update = \action model -> (Textfield.update action model, Effects.none)
+  }
+
+
+embed : 
+  Component submodel action a ->            -- Given a "Component submodel ..."
+  (model -> States submodel) ->             -- a getter 
+  (States submodel -> model -> model) ->    -- a setter
+  Int ->                                    -- an id for this instance
+  submodel ->                               -- an initial model for this instance
+  Component model action a                  -- ... produce a "Component model ..."
+
+embed component get set id model0 = 
+  let 
+    get' model = 
+      Dict.get id (get model) |> Maybe.withDefault model0
+
+    set' submodel model = 
+      set (Dict.insert id submodel (get model)) model 
+
+    view addr model = 
+      component.view addr (get' model)
+
+    update action model = 
+      component.update action (get' model)
+        |> map1st (flip set' model)
+  in 
+    { view = view
+    , update = update
+    }
+
+
+instance : ((Action State) -> action) -> Component State a b -> View State action b
+instance f component addr state = 
+  component.view 
+    (Signal.forwardTo addr (pack component.update >> f))
+    state 
+
+{-
+f id = 
+
+  embed buttonComponent .button (\x y -> { y | button = x}) id (Button.model True)
+-}
+
+buttonInstance : ((Action State) -> action) -> Int -> View State action (List Style -> List Html -> Html)
+buttonInstance f id = 
+  embed buttonComponent .button (\x y -> { y | button = x}) id (Button.model True)
+    |> instance f
+
+
+textfieldInstance f id = 
+  embed textfieldComponent .textfield (\x y -> { y | textfield = x}) id (Textfield.model)
+    |> instance f
+