A menor versao possivel do redux

NanoRedux.js

function createStore(reducer) {
  let state
  let listeners = []
 
  const getState = () => state

  const subscribe = (listener) => {
    listeners.push(listener)
    return () => {
      listeners = listeners.filter((l) => l !== listener)
    }
  }
  
  const dispatch = (action) =>  {
    state = reducer(state, action)
    listeners.forEach((listener) => listener())
  }
  return {
    getState,
    subscribe,
    dispatch,
  }
}