Question

In C#, I can do this:

class Program {     static void Main(string[] args)     {         List<Animal> animals = new List<Animal>();          animals.Add(new Dog());         animals.Add(new Cat());          foreach (Animal a in animals)         {             Console.WriteLine(a.MakeNoise());             a.Sleep();         }     } }  public class Animal {     public virtual string MakeNoise() { return String.Empty; }     public void Sleep()     {         Console.Writeline(this.GetType().ToString() + ' is sleeping.');     } }  public class Dog : Animal {     public override string MakeNoise()     {         return 'Woof!';     } }  public class Cat : Animal {     public override string MakeNoise()     {         return 'Meow!';     } } 

Obviously, the output is (Slightly paraphrased):

• Woof
• Dog is Sleeping
• Meow
• Cat is Sleeping

Since C# is often mocked for its verbose type syntax, how do you handle polymorphism/virtual methods in a duck typed language such as Ruby?

Answer 1

edit: added more code for your updated question

disclaimer: I haven’t used Ruby in a year or so, and don’t have it installed on this machine, so the syntax might be entirely wrong. But the concepts are correct.

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The exact same way, with classes and overridden methods:

class Animal     def MakeNoise         return ''     end     def Sleep         print self.class.name + ' is sleeping.\n'     end end  class Dog < Animal     def MakeNoise         return 'Woof!'     end end  class Cat < Animal     def MakeNoise         return 'Meow!'     end end  animals = [Dog.new, Cat.new] animals.each {|a|     print a.MakeNoise + '\n'     a.Sleep }