React Redux 减速机

Question

I'm a newbie to react-redux and want to know the difference between the following two code snippets used within the reducer.

This is the first code snippet:

[types.GET_TAGS]: (state, {payload}) => {
    return {
        ...state,
        tagData:null
    };
},

And the second code snippet is this:

[types.GET_TAGS]: (state, { payload }) => ({
    ...state,
    tagData: null
}),

In the first code snippet return statement has been used... What's the difference?

Answer 1

No difference, second is short notation, word return is omitted.

Answer 2

There's nothing related to react-redux out here. The difference is in the notation of the arrow function.

The second code is a short notation of the first one.

For eg,

const a = () => {return 1};
a(); // will return 1

Similarly,

const b  = () => (1);
b(); // will return 1

Answer 3

There are no difference. It's a shortcut when you want to "return" something directly.

Example on a normal function:

const test = () => {
  return 'hello'
}

since we're not doing anything and we just want to return the 'hello' directly, we can do a shorter code which is:

const test = () => 'hello'