applyMiddleware(thunkMiddleware)(createStore)(reducers)连续3个括号什么意思?

Question

redux创建store

第一种：

const store = createStore(reducers, applyMiddleware(thunkMiddleware));

第二种：

const store = applyMiddleware(thunkMiddleware)(createStore)(reducers);

两种写法达成的效果一样。

第一种很好理解，第二种看不明白，有没有大佬解释一下？

Answer 1

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Answer 2

不知道是否已经解决这个问题调用方式：`createStroe(reducer,preloadedState,enhancer)` 其中`applyMiddleware(...middlewares)`也就是参数enhancer,在createStore源码里，当enhancer有值时，调用方式如下：    `enhancer(createStore)(reducer, preloadedState)`，也就变成了：    `applyMiddleware(...middlewares)(createStore)(reducer,preloadedState)`