TheSeamau5

import Graphics.Element exposing (Element)
import Graphics.Collage exposing (..)
import Color
import Signal 
import Time


-- Play with this value and hot swap the code
gravity = -9.8
--

TheSeamau5

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

type alias Vector = 
  { x : Float , y : Float }
  
----------------------------------

type alias Init options state effect = options -> (state, effect) 
type alias Update action state effect = action -> state -> (state, effect)

TheSeamau5

type alias Update action state = action -> state -> state
type alias View action state = Address action -> state -> Html
type alias Init options state = Vector -> options -> state

TheSeamau5

updateN : Int -> (a -> a) -> List a -> List a
updateN n f list = 
  List.indexedMap (\index value -> if index == n then f value else value) list

TheSeamau5

Type signatures for elm-html components (without effects)

First, consider the following type aliases

type alias Init options state = options -> state
-- type alias Init option state = Vector -> options -> state
-- alternative version if using inline styles

type alias Update action state = action -> state -> state

TheSeamau5

import Graphics.Element exposing (show)

type Mappable a b ma mb = Mappable
  { map : (a -> b) -> ma -> mb }
  
  
map : (a -> b) -> ma -> { ext | mappable : Mappable a b ma mb } -> mb
map f m {mappable} = case mappable of
  Mappable {map} -> map f m
  

TheSeamau5

import Html exposing (Html, Attribute)
import Html.Attributes 
import Html.Events
import Json.Decode exposing (Decoder, (:=))
import List
import Signal exposing (Address)
import StartApp
import Array exposing (Array)
import Window
 

TheSeamau5

import Html exposing (Html)
import Html.Attributes
import Time
import Mouse
import Signal
 
-----------
 
infixl 2 =>
(=>) = (,)

TheSeamau5

import Html exposing (Html)
import Html.Attributes
import Time
import Mouse
import Signal
 
-----------
 
infixl 2 =>
(=>) = (,)

TheSeamau5

type alias Spring a = 
  { stiffness   : Float 
  , friction    : Float 
  , position    : a 
  , velocity    : a 
  , destination : a 
  }