First off, very cool example.

I'm playing around with this pattern on a help form. The form has its typical onChange events that update the state, etc. But what happens when the form is submitted? How do I get that information up to the parent?

Right now I'm having to parse through all the action messages and delegate them to the project updater. This is pretty tedious.

let Help = {
  view: function({state, dispatch}) {
    return (
      state.success ? 
        <HelpFormSuccess state={state} dispatch={dispatch}/> : 
        <HelpForm state={state} dispatch={dispatch}/>
    )
  },
  update: function(state=initialState, action) {
    switch (action.type) {
      case ON_ERROR:
        //...
      case VALIDATE_AND_SUBMIT:
        //...
      case ON_CHANGE:
        return HelpForm.update(state, action)
      default:
        return state
    }
  }
}

It would be cool it there was a way to indicate whether an action is meant to be dispatched to itself, or up to the parent. How does Elm deal with this? I understand this is just a toy example, but its really cool and I think it would be really power if its done right.