Discussion on: Is JS an OOP Language?

// Classes have implicit interface definitions
// plus the ability to create a new object of that type
public class Person
{
    // implicit interface properties of...
    string lastName;
    string firstName;
}
// if there's a method  anywhere in the project like this:

setName(Person person){
  // the parameter is a concrete Person object
  // that has implicit interfaces of lastName and firstName properties.
}

// but what about this?
setName(iPerson person){}

// and assume this:
// a definition of an interface
interface IPerson{
  string lastName;
  string firstName;
}
// here we have the same exact thing happening, 
// but the parameter is asking for an object of type interface
// and not a concrete person object.

// The only difference is that we cannot create a new instance of an interface. 
// To do that we'd need this.
// Change Person to implement the interface
class Person:IPerson{
  string lastName;
  string firstName;
}

//create a new person object which passes the interface test
var person = new Person()
// Works due to our Person Class
// implementation of iPerson
setName(iPerson person){}