This SUPERIOR way ov defining enums in JavaScript!

#javascript #webdev

The Standard Way ov Defining An Enum

In JavaScript, the standard way to define an enum – according to the TypeScript compiler – is:

"use strict";
var Fruit;
(function (Fruit) {
  Fruit[Fruit["BANANA"] = 0] = "BANANA";
  Fruit[Fruit["ORANGE"] = 1] = "ORANGE";
  Fruit[Fruit["APPLE"]  = 2] = "APPLE";
})(Fruit || (Fruit = {}));

Or, if we strip the (unnecessary) mapping from number to string, we can do:

"use strict";
var Fruit = {
  "BANANA": 0,
  "ORANGE": 1,
  "APPLE":  2
};

The Better Way ov Defining An Enum

... However, there is a better way to define an enum – and the method will ensure:

the enum values are unique,
the values can't be overriden,
the definition is hoisted.

var Fruit;
{
  Fruit = Object.defineProperties((Fruit = Object.create(null)), {
    BANANA: {writable: false,  value: Symbol("BANANA")},
    ORANGE: {writable: false,  value: Symbol("ORANGE")},
    APPLE:  {writable: false,  value: Symbol("APPLE")}
  });
}