Discussion on: If/else or just if?

[The Jared Wilcurt]

There isn't much value in the else since the first conditional results in a return, however having it aids in readability in this case by grouping these two similar conditions. but having a final return outside of a condition is a best practice to ensure you don't mistakenly return undefined. The trailing else should be removed if it is just a return statement.

function (value) {
  if (typeof(value) === 'string') {
    return 'A';
  } else if (value === null || value === undefined) {
    return 'B';
  }
  return value;
}

Though in many cases, a map works better than a bunch of if/else's.

function (state) {
  const states = {
    indiana: 24,
    ohio: 36,
    florida: 19
  };

  return states[state] || 0;
}

Using the mapped approach eliminates any need for switch statements.

Also, don't abbreviate your code, there is no benefit gained from shaving off a few characters. Let the uglifier worry about that. Your goal should always be readability above all else until something is noticeably slow.