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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Posted by jeporcher
jeporcher
11,843 Points

Help refactoring long Array.reduce() call

Hello all,

The only way I could make the following reduce() call work feels long-winded and I wonder how one could refactor the code so it looks cleaner. Any help much appreciated.

numberOf503 = phoneNumbers.reduce((count, phone) => {
  if (phone.slice(1,4) === '503') {
    return count + 1;
  } else {
    return count;
  }
}, 0);

Best, J.

1 Answer

Greg Kaleka
Greg Kaleka
39,021 Points
Greg Kaleka
Greg Kaleka
39,021 Points

Looks pretty good to me. Very readable and understandable. Don't get too caught up in wanting your code to look "elegant". The most important thing is that you can quickly understand what's happening in your code.

The only thing you could do to make this a bit shorter if you wanted would be to eliminate the else clause. Let me know if you don't see why we can do this.

numberOf503 = phoneNumbers.reduce((count, phone) => {
  if (phone.slice(1,4) === '503') {
    return count + 1;
  }
  return count;
}, 0);

Cheers :beers:

-Greg

jeporcher
jeporcher
11,843 Points

Thanks a lot for your input!