Syntax comparison of Classes and Inheritance using CoffeeScript, Dart, and TypeScript.

DocWho.coffee

class Character
	@name

	constructor: (person, @role) ->
		@name = "#{person.firstname} #{person.lastname}"

	toString: () ->
		"#{@role} played by #{@name}"


class Doctor extends Character

	constructor: (person, @doctor) ->
		super person, "The Doctor"

	toString: () ->
		"#{super.toString()}, The #{@doctor} Doctor"

class Companion extends Character

	constructor: (person, role, @companionTo) ->
		super person, role

	toString: () ->
		"#{super.toString()}, companion of the #{@companionTo} Doctor"


eleventh = new Doctor({firstname: "Matt", lastname: "Smith"}, 11)
amy = new Companion({firstname: "Karen", lastname: "Gillan"}, "Amy Pond", 11)
clara = new Companion({firstname: "Jenna-Louise", lastname: "Coleman"}, "Clara Oswald", 11)
console.log eleventh.toString()
console.log amy.toString()
console.log clara.toString()

DocWho.dart

class Person {
  String firstname;
  String lastname;
  Person(this.firstname, this.lastname);

}

class Character {
  String name;
  String role;
  
  Character(Person person,  this.role) {
    this.name = "${person.firstname} ${person.lastname}";
  }
  
  toString() => "${this.role} played by ${this.name}";

}

class Doctor extends Character {
  int doctor;
  
  Doctor(Person person, this.doctor) : super(person, "The Doctor");
 
  toString() => "${super.toString()}, The ${this.doctor} Doctor";

}

class Companion extends Character {
  int companionTo;
  
  Companion(Person person, String role, this.companionTo): super(person, role);
  
  toString() => "${super.toString()}, companion of the ${this.companionTo} Doctor";

}

void main() {
  var eleventh = new Doctor(new Person("Matt", "Smith"), 11);
  var amy = new Companion(new Person("Karen","Gillan"), "Amy Pond", 11);
  var clara = new Companion(new Person("Jenna-Louise","Coleman"), "Clara Oswald", 11);
  print(eleventh);
  print(amy);
  print(clara);
}

DocWho.ts

interface Person {
    firstname: string;
    lastname: string;
}

class Character {
    public name: string;
 
    constructor(person: Person, public role: string) {
        this.name = person.firstname + " " + person.lastname;
    }
 
    toString(): string {
        return  this.role + " played by " + this.name;
    }

}

class Doctor extends Character {

    constructor(person: Person, public doctor: number) {
        super(person, "The Doctor");
    }

    toString(): string {
        return  super.toString() + ", The " + this.doctor + " Doctor";
    }

}

class Companion extends Character {

    constructor(person: Person, role: string, public companionTo: number) {
        super(person, role);
    }

    toString(): string {
        return  super.toString() + ", companion of the " + this.companionTo + " Doctor";
    }

}

var eleventh = new Doctor({firstname: "Matt", lastname: "Smith"}, 11);
var amy = new Companion({firstname: "Karen", lastname: "Gillan"}, "Amy Pond", 11);
var clara = new Companion({firstname: "Jenna-Louise", lastname: "Coleman"}, "Clara Oswald", 11);
console.log(eleventh.toString());
console.log(amy.toString());
console.log(clara.toString());