Enums in Javascript with ES6

JavaScript doesn't natively support enums like languages such as TypeScript or Java, but you can simulate enum-like behavior using ES6 features. Enums (short for "enumerations") are useful when you want to define a set of named constants that represent a group of related values — like days of the week, user roles, or states.

 Using const and Objects

The most common way to create enums in JavaScript is with a const object.

const Colors = {

  RED: 'RED',

  GREEN: 'GREEN',

  BLUE: 'BLUE'

};

console.log(Colors.RED); // Output: RED

• This method is simple and keeps your values organized and readable.
  
• It's good for grouping related constants together.
  

 Using Object.freeze() for Immutability

To prevent changes to your enum object, use Object.freeze():

const Status = Object.freeze({

  PENDING: 'PENDING',

  IN_PROGRESS: 'IN_PROGRESS',

  COMPLETED: 'COMPLETED'

});

This makes the enum immutable — no one can accidentally modify or add properties.

 Using Symbol for Unique Values

If you need unique and non-string values, use ES6 Symbol:

const Direction = {

  UP: Symbol('UP'),

  DOWN: Symbol('DOWN'),

  LEFT: Symbol('LEFT'),

  RIGHT: Symbol('RIGHT')

};

Symbols guarantee uniqueness, even if two enums have the same name.

 Summary:

• Use objects for basic enums.
  
• Use Object.freeze() for safety.
  
• Use Symbol for uniqueness and to avoid value collisions.
  

While JavaScript doesn’t offer true enums natively, these ES6 patterns give you the power and flexibility to simulate them effectively.