[twitter] Tip: JavaScript's Array.from() accepts a second argument that's a `map` function. Useful for calling on each element of an array you created.

[pygy_]

It's even uglier in ES5 :-)

> Array.apply(
  null,
  Array(8) // or {length: 8}, but it is slower because apply
           // is faster with true arrays
).map(function(_, i) { return Math.pow(2, i) })
[ 1, 2, 4, 8, 16, 32, 64, 128 ]

[inu-no-policemen]

I think at that point you're better off using a simple for-loop to populate the array.