迷你redux实现，redux是如何进行实现的？

export function createStore(reducer){
let currentState={}
let currentListeners=[]
function getState(){
return currentState
}
function subscribe(listener){
currentListeners.push(listener)
}
function dispatch(action){
currentState=reducer(currentState,action)
currentListeners.forEach(v=>v())
return action
}
return {getState,subscribe,dispatch}
}