Page 128 - JavaScript

When using implicit returns, object literals must be wrapped in parenthesis so that the curly braces
are not mistaken for the opening of the function's body.

const foo = () => { bar: 1 } // foo() returns undefined
const foo = () => ({ bar: 1 }) // foo() returns {bar: 1}

Explicit Return

Arrow functions can behave very similar to classic functions in that you may explicitly return a
value from them using the return keyword; simply wrap your function's body in curly braces, and
return a value:

const foo = x => {
return x + 1;
}

foo(1); // -> 2

Arrow functions as a constructor

Arrow functions will throw a TypeError when used with the new keyword.

const foo = function () {
return 'foo';
}

const a = new foo();

const bar = () => {
return 'bar';
}

const b = new bar(); // -> Uncaught TypeError: bar is not a constructor...

Read Arrow Functions online: https://riptutorial.com/javascript/topic/5007/arrow-functions

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