Published at
Updated at
Reading time
1min
This post is part of my Today I learned series in which I share all my web development learnings.

I followed a Twitter conversation between Surma from Google and Andrea Giammarchi in which Andrea mentionied that Array.from accepts a second argument. 😲

console.log(Array.from([1, 2, 3], x => x + x));
// [2, 4, 6]

The snippet they discussed showed functionality to call a callback X times.

// call a callback `length` times
Array.from({length}, () => callback())

// or generate a random emoji Array
Array.from(
  {length: 7},
  (v, i) => String.fromCodePoint(
    129300 + Math.floor(Math.random() * 20)
  )
);

// [ '🤡', '🤗', '🤥', '🤛', '🤤', '🤦', '🤔' ]

You can read more about Array.from on MDN.

Was this TIL post helpful?
Yes? Cool! You might want to check out Web Weekly for more quick learnings. The last edition went out 2 days ago.

Related Topics

Related Articles

About the author

Stefan standing in the park in front of a green background

Frontend nerd with over ten years of experience, "Today I Learned" blogger, conference speaker, Tiny helpers maintainer, and DevRel at Checkly.