JS: transform object to primitive

objectToPrimitive.js

function transform(hint) {
  return hint == 'string' ? this.name : this.height  
}

let man = {
  name: 'Evgeniy',
  height: 185,
  [Symbol.toPrimitive]: transform
}

let woman = {
  name: 'Daria',
  height: 155,
  [Symbol.toPrimitive]: transform
}

let animal = {
  name: 'Ars',
  height: 20,
  [Symbol.toPrimitive](hint) {
    return hint === 'string' 
      ? this.name + `(animal)` : this.height
  }
}

console.log(man + woman + animal) // expected: 360