avoid-mutation.js

/* 

  You have to understand that each object 
  has a unique identity in JavaScript
  
  console.log(new Object() === new Object()); 
  
*/

console.log({} === {}); // false

/* 

  But when you assign `fiz` to `baz`, `baz` points to the same object as `fiz`.
  Since `fiz` and `baz` are the same thing, when you change `baz`, `fiz` reflects the same change.
  
*/

const fiz = { foo: 'bar' };
const baz = fiz;