redux with a generator

redux.js

export const createStore = (reducer, state = {}) => {
  let subs = []

  const store = (function * () {
    while (true) {
      const event = yield null
      state = reducer(state, event)
      subs.forEach(fn => fn(state))
    }
  })

  // prime generator
  store.next({ type:"@@init|0" })
  store.next({ type:"@@init|1" })

  const getState  = () => state
  const dispatch  = ev => store.next(ev)
  const subscribe = fn => {
    subs.push(fn)
    fn(state)
    unsubbed = false
    return () => {
      if (unsubbed) return
      unsubbed = true
      subs.splice(subs.indexOf(fn), 1)
    }
  }

  return { getState, dispatch, subscribe }
}