此粗箭头如何在此代码中运行？

Question

I was looking at this code here and wondering how the arrow function is working here. Is it related to the concept of the lexical this?

function multiplier(factor) {
  return number => number * factor;
 }

 const multiplier = (factor) => {
   return number => number * factor;
};

let twice = multiplier(2);
console.log(twice(5));

For example, I can refactor this like so:

const multiplier = (factor) => number => number * factor;

let twice = multiplier(2);
console.log(twice(5));

And it still works. So am I in the ballpark of how the fat arrow is being used here?

Answer 1

function multiplier(factor) {
    return number => number * factor;
}

is simply equivalent to

function multiplier(factor) {
    return function(number) { return number * factor };
}

There's no this involved here.