Javascript getters/setters quick demo - expanded from Node.js Design Patterns (Second Edition) - https://www.nodejsdesignpatterns.com/

index.js

const person = {
  name: 'George',
  surname: 'Boole',
  get fullname () {
    console.log('** getting fullname')
    return this.name + ' ' + this.surname
  },
  set fullname (fullname) {
    console.log('** setting fullname to', fullname)
    let parts = fullname.split(' ')
    this.name = parts[0]
    this.surname = parts[1]
  }
}

console.log(person.fullname) // (** getting fullname)  "George Boole"
console.log(person.fullname = 'Alan Turing') // (** setting fullname to Alan Turing') "Alan Turing"
console.log(person.name) // “Alan"
console.log(person.fullname) // (** getting fullname) "Alan Turing"

// inspecting the object
console.log(person) // { name: 'Alan', surname: 'Turing', fullname: [Getter/Setter] }