Default method parameters can access object properties

defafultObjectProps.js

class Person {
  constructor (name) {
    this.name = name
    this.defaultSalultation = 'Dr.'
  }

  sayHello (salutation = this.defaultSalultation) {
    return `Hello ${salutation} ${this.name}`
  }
}

const dr1 = new Person('James Baldwin')
console.log(dr1.sayHello('The One and Only Mr.')) // Hello The One and Only Mr. James Baldwin

const dr2 = new Person('David Deutsch')
console.log(dr2.sayHello()) // Hello Dr. David Deutsch