JS | Value vs Reference - 2 Rabbits and a Magic Hat

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JS | Value vs Reference

This exercise is not mandatory, however it may be a good example for understanding the "variables created in functions" and concept of "passing objects (object, arrays and functions) by reference" in JavaScript.

The Riddle: 2 Rabbits and a Magic Hat 🐰 🐇 🎩

Given the below code, without running the code in the console try to answer what will be the output of 2 console.log statements on the bottom.

function magicHat(obj) {
  obj.age = 10;
  obj = { name: 'John', age: 20 };
  return obj;
}
  
let rabbit1 = { name: 'Rapha', age: 30 };
  
let rabbit2 = magicHat(rabbit1);
  
// console.log('rabbit1 ->', rabbit1); // -> ?
// console.log('rabbit2 ->', rabbit2); // -> ?

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If you were unable to come up with the answer after some time, and/or you are not a fan of solving riddles 😁 check this link with the answer and explanation.