JavaScript · Senior · Question 21 of 75

How do you deep-freeze an object?

function deepFreeze(obj) {
  for (const value of Object.values(obj)) {
    if (value && typeof value === "object") deepFreeze(value);
  }
  return Object.freeze(obj);
}

✓Correct answer: Recursively freeze nested objects and then the object itself
2Call Object.freeze(obj, { deep: true })
3Use Object.seal, which works all the way down

Explanation

Object.freeze is shallow, and Object.seal only prevents adding and removing properties. Recursion walks the tree; for circular references, keep visited objects in a WeakSet. freeze has no deep option.

How do you deep-freeze an object?

Explanation

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