Can global constants be declared in JavaScript?

Question

If so, what is the syntax for such a declaration?

Answer 1

If you only care about supporting newer browsers (or are using a transpiler such as Babel to support older browsers) you can do the following:

1. Create a settings.js file with whatever constants you want and export them:

export const FRUIT = "kiwi";
export const VEGETABLE = "carrot";

2. In files that you want to use them you could then import them as follows:

import * as Settings from './settings.js'

3. Then to use the constants do something like this:

console.log("The unchangeable fruit is " + Settings.FRUIT);

This is a much cleaner approach than trying to implement a global constant, especially when you have multiple JavaScript files that you want to use the constants in.