ES6 Classes & Constructors

What's an advantage of using the class syntax instead of the factory function?

function createPerson(name, age) {
  return {
    name,
    age,
    greet() {
      return `Hello, I'm ${this.name}`;
    }
  };
}

class Person {
  constructor(name, age) {
    this.name = name;
    this.age = age;
  }
  
  greet() {
    return `Hello, I'm ${this.name}`;
  }
}

Classes are faster
Classes use less memory for methods
Classes use less memory for methods because: 1) Class methods are defined on the prototype and shared across instances, 2) Factory function methods are created anew for each object, 3) With many instances, classes can be more memory efficient, 4) The prototype chain is more efficient for method lookup, 5) This is particularly important for applications creating many instances, 6) However, factory functions have their own advantages like encapsulation and closure-based privacy, so each approach has its place.
Classes make debugging easier
Factory functions are always worse

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