Object.freeze() method

JavaScript
1

I’ve completed and passed the ES6: Prevent Object Mutation lesson using the Object.freeze() method.
Here’s the code:

  'use strict';
  const MATH_CONSTANTS = {
    PI: 3.14
  };
Object.freeze(MATH_CONSTANTS);//Line 6
  try {
    MATH_CONSTANTS.PI = 99;
  } catch(ex) {
    console.log(ex);
  }
  return MATH_CONSTANTS.PI;
}
const PI = freezeObj();
console.log(PI)//Logs 3.14 as expected

The code passed but I’m getting the following error:

[TypeError: Cannot assign to read only property 'PI' of object '#<Object>']

Did I do something wrong?

2

That’s exactly what is supposed to happen. Because you froze PI, attempting to assign it generates an exception. The catch block captures that exception and prints it with console.log(ex).

3

Okay thanks very much