Using Symbol.for to create a global instance

We've seen how to create unique symbols to use as keys in a local context. However, sometimes, we want to be able to interact with a data structure. Symbols can be made to work in this case as well.

Getting ready

This recipe assumes that you already have a workspace that allows you to create and run ES modules in your browser. If you don't, refer to the first two chapters.

How to do it...

1. Open your command-line application and navigate to your workspace.
2. Create a new folder named 11-02-symbol-for-global.
3. Copy or create an index.html that loads and runs a main function from main.js.
4. Create a main.js file that defines a main function that creates a couple of sets of Symbols, using Symbol.for, with string and number arguments. Compare the numeric symbols with a number as string:

// main.js 
export function main() { 
  const usLaunchLocation = Symbol.for('Kennedy Space Center'); 
  const duplicateLaunchLocation = Symbol.for('Kennedy Space 
  Center'); 
 ...