Javascript Constants in ES6

Question

What would be the preferred way to create constants in javascript, specifically with ES6?

Currently I have a constants class which has methods that return the string I'm looking for.

 class Constants {
    constructor() {}

    SOMECONSTANT() {
       return 'someconstant';
    }
 }

Answer 1

For backwards compatibility, I would create a read-only property of the encapsulating object, which could be the global object:

Object.defineProperty(this, 'CONST', {
  value: 123,
  writable: false
});

See: Object.defineProperty - writable attribute

Otherwise, ES6 has a const keyword.

const name1 = value1 [, name2 = value2 [, ... [, nameN = valueN]]];

See const.