Shortening a Javascript if-else structure

Question

The code I have is:

 var level = function (d) {
    if (value(d) > median + stdev) {
        return 1;
    } else if (value(d) > median) {
        return 2         


        

Answer 1

I don't see much room for improvements which could guarantee the same readability of the starting case. If you are really returning integers, and they aren't there just for the sake of this example, I would suggest you to return something more meaningful.

You could for sure compute value(d) just once

var level = function (d) {
  var dValue = value(d);
  if (dValue > median + stdev) {
    return 1;
  } else if (dValue > median) {
    return 2;
  } else if (dValue > median - stdev) {
    return 3;
  } else {
   return 4;
  }
};

Also, you might want to avoid multiple returns, or maybe you don't, for me they're the same, each has advanges/disadvantages:

var level = function (d) {
  var dValue = value(d),
      code = 4;
  if (dValue > median + stdev) {
    code = 1;
  } else if (dValue > median) {
    code = 2;
  } else if (dValue > median - stdev) {
    code = 3;
  } 
  return code;
};

If you assign a meaningful name to code you are giving even more information to the guy who is reading your code.