JavaScript · Senior · Question 61 of 75

What does `Symbol.toPrimitive` control?

const price = {
  [Symbol.toPrimitive](hint) { return hint === "number" ? 42 : "$42"; },
};

✓Correct answer: How the object converts to a primitive in +price, ${price} and comparisons
2Whether the object can be frozen
3How the object is serialized to JSON

Explanation

The hint is "number", "string" or "default". Without it, JS calls valueOf and toString in an order depending on the hint.

Further reading

javascript.info: Object to primitive conversion ↗

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