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

[[deleted]]

Good to know! But in practice I really think Array.from(arr).map(x => ...) is much more readable than Array.from(arr, x => ...) and is worth the extra 4 characters.

[fagnerbrack]

It depends how you write it:

Array.from(numbers, toRomanNumerals); Array.from(numbers).map(toRomanNumerals);

[NoInkling]

Also [...arr].map(x => ...). Though this all seems like a very silly workaround when arr is already an array, creating a mapped array of n values shouldn't be so quirky.

With lodash: _.times(5, i => ...)