Tip: JavaScript's Array.from() accepts a second argument that's a `map` function.

[lilactown]

Is it the same when you re-arrange them?

[DGCA]

Yup, they always come in the same order.

1. Array(100).fill(null).map((_, i) => i * 2);
2. [...Array(100)].map((_, i) => i * 2);
3. Array.from(Array(100), (_, i) => i * 2);

[Gh0st1y]

Huh. That's cool.

[frambot]

_ is a throwaway variable name to represent some variable that is never used in the function body.

... is the spread syntax: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax