Repeating Strings in JavaScript

While cleaning up some of my old notes today, specifically stuff I jotted down that would make for a good blog topic, I happened upon the topic of repeating strings in JavaScript.

Things are really easy in ES6+, but if you happen to still support Internet Explorer for some crazy reason, or just want to slum it like it’s the good ol’ days, we can repeat strings by way of a loop:

function repeat(string, repeats) {
  let repeated = ''

  for (let i = 0; i < repeats; i += 1) {
    repeated += string;
  }

  return repeated;
}

repeat('Testing', 100);

Not the most elegant thing in the world, and could probably golf it down a bit.

But, since we’re living in an ES6 world, there’s no reason to spin our wheels on that, and can simply leveraged String.prototype.repeat which accepts a single argument to tell it how many times to repeat.

The aforementioned old school example can be expressed as such:

'Testing'.repeat(100);

And we can call it a day!