JavaScript Demo: Symbol.toPrimitive

const object1 = {
  [Symbol.toPrimitive](hint) {
    if (hint == 'number') {
      return 42;
    }
    return null;
  }
};

console.log(+object1);
// expected output: 42

JavaScript Demo: Symbol.toPrimitive

​x
const object1 = {
  [Symbol.toPrimitive](hint) {
    if (hint == 'number') {
      return 42;
    }
    return null;
  }
};
​
console.log(+object1);
// expected output: 42
​