Object Descriptors & Property Flags

What value will be output when attempting to modify a non-writable property?

const obj = {};
Object.defineProperty(obj, 'id', {
  value: 42,
  writable: false,
  enumerable: true,
  configurable: true
});

obj.id = 100;
console.log(obj.id);

100
42
The code will log 42 because: 1) The property 'id' is defined with writable: false, 2) When a property is non-writable, assignments are silently ignored in non-strict mode, 3) The original value 42 is preserved despite the attempt to change it to 100, 4) No error is thrown because this code runs in non-strict mode, 5) The property remains enumerable and configurable as specified, 6) This demonstrates how the writable flag protects a property value from being changed once set.
undefined
Error will be thrown

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