Solution

'abcdabcdabcdabcdabcd'.match(/.{1,4}/g)
// ['abcd', 'abcd', 'abcd', 'abcd', 'abcd']

Here's original StackOverflow answer.

Context

In today's Advent of Code challenge, I had to simulate drawing pixels on 40x6 CRT screen. First I computed lit and dark pixels, and got the following string, which I needed to map on 40x6 screen.

const screen = '##..##..##..##..##..##..##..##..##..##..###...###...###...###...###...###...###.####....####....####....####....####....#####.....#####.....#####.....#####.....######......######......######......###########.......#######.......#######.....';

const formattedScreen = screen
  .match(/.{1,40}/g)
  .join('\n');

After logging that in the console, I got expected output which contained 8 capital letters - the answer to the challenge: PGHFGLUG

###...##..#..#.####..##..#....#..#..##..
#..#.#..#.#..#.#....#..#.#....#..#.#..#.
#..#.#....####.###..#....#....#..#.#....
###..#.##.#..#.#....#.##.#....#..#.#.##.
#....#..#.#..#.#....#..#.#....#..#.#..#.
#.....###.#..#.#.....###.####..##...###.