在React / Redux中的箭头功能内使用方括号有什么意义

Question

Given the following react-redux code:

const TextListContainer = ({ items, actions }) => (
    <TextList items={items} actions={actions} />
)

Why are normal brackets used here instead of curly brackets?

---

To further illustrate my question:

NORMAL FUNCTION:

const someFn = something => {
    //...
}

BRACE STYLE FUNCTION:

const someFn = something => (
    //...
)

This style of code is copied from here: https://github.com/reactjs/redux/blob/master/examples/todomvc/src/containers/App.js

Answer 1

() => something , where something doesn't start with { , returns something .

With () => { , { is interpreted as the start of a function body, so you have to explicitly return something. To get around this, eg if you wanted to return an object, you can use ( :

() => ({ some object })

Using it in other situations is a question of consistency.

Answer 2

Basically {} is used when there is function body and you need to return a particular value based on the computations in the function. A simple example of a function to add 1 if value is more than 10 else subtract 1 .

(value) => {
  if(value > 10){
    return value + 1; 
  }
  return value - 1;
}

On the other hand if there is really a simple function like returning a boolean value.you could do something like this:

(num) => (num > 100)

returns a boolean. Simple and clean.