Non-mutating array push method equivalent

Question

I'd like to add a new element to an array in a non-mutating way. In JS, I can do this:

var new_arr = arr.concat(3)

instead of this:

arr.push(3)

How can I do the same thing in Ruby? The concat method in Ruby is mutating.

Answer 1

As simple as this:

new_arr = arr + [3]

Answer 2

I'll add another solution using array splats that might seem less awkward:

new_arr = [*arr, 3]