componentconstructors.elm

import Html exposing (Html)
import Signal exposing (Address)

type alias Init options state effect 
  = options -> (state, List effect)
  
type alias Update action state effect 
  = action -> state -> (state, List effect)
  
type alias View action state 
  = Address action -> state -> Html
  
  
type alias Component options action state effect
  = { init   : Init options state effect
    , update : Update action state effect
    , view   : View action state
    }
    
    
simple : { init   : state
         , update : action -> state -> state
         , view   : state  -> Html
         }
      -> Component Void action state Never
simple {init, update, view} = 
  { init   = always (init, [])
  , update = (\a s -> (update a s, []))
  , view   = always view
  }
  


container : { child  : context -> Component childOptions childAction childState childEffect
            , init   : (context -> Init childOptions childState childEffect)  -> Init options state effect
            , update : (context -> Update childAction childState childEffect) -> Update action state effect
            , view   : (context -> View childAction childState) -> View action state
            }
         -> Component options action state effect
container {child, init, update, view} = 
  { init   = init   (child >> .init)
  , update = update (child >> .update)
  , view   = view   (child >> .view)
  }




container2 : { child1 : context1 -> Component child1Options child1Action child1State child1Effect
             , child2 : context2 -> Component child2Options child2Action child2State child2Effect
             , init   : (context1 -> Init child1Options child1State child1Effect) 
                     -> (context2 -> Init child2Options child2State child2Effect)
                     -> Init options state effect
             , update : (context1 -> Update child1Action child1State child1Effect) 
                     -> (context2 -> Update child2Action child2State child2Effect)
                     -> Update action state effect
             , view   : (context1 -> View child1Action child1State) 
                     -> (context2 -> View child2Action child2State)
                     -> View action state
             }
          -> Component options action state effect
container2 {child1, child2, init, update, view} = 
  { init   = init   (child1 >> .init)   (child2 >> .init)
  , update = update (child1 >> .update) (child2 >> .update)
  , view   = view   (child1 >> .view)   (child2 >> .view)
  }



  
simpleContainer : { child : Component childOptions childAction childState childEffect
                  , init  : Init childOptions childState childEffect -> Init options state effect
                  , update : Update childAction childState childEffect -> Update action state effect
                  , view   : View childAction childState -> View action state
                  }
               -> Component options action state effect
simpleContainer {child, init, update, view} = 
  { init   = init child.init
  , update = update child.update
  , view   = view child.view
  }
  
  
  
 
simpleContainer2 : { child1 : Component child1Options child1Action child1State child1Effect
                   , child2 : Component child2Options child2Action child2State child2Effect
                   , init   : Init child1Options child1State child1Effect 
                           -> Init child2Options child2State child2Effect
                           -> Init options state effect
                   , update : Update child1Action child1State child1Effect 
                           -> Update child2Action child2State child2Effect
                           -> Update action state effect
                   , view   : View child1Action child1State 
                           -> View child2Action child2State
                           -> View action state
                   }
                -> Component options action state effect
simpleContainer2 {child1, child2, init, update, view} = 
  { init   = init   child1.init   child2.init
  , update = update child1.update child2.update
  , view   = view   child1.view   child2.view
  }

  
  
  
  
type Never = Never Never
type Void  = Void