title: Optional parameters for interfaces
body: <p>Using c# 4.0 -- building an interface and a class that implements the interface. I want to declare an optional parameter in the interface and have it be reflected in the class. So, I have the following:</p>
  
  <pre><code> public interface IFoo
   {
        void Bar(int i, int j=0);
   }
  
   public class Foo
   {
        void Bar(int i, int j=0) { // do stuff }
   }
  </code></pre>
  
  <p>This compiles, but it doesn't look right. The interface needs to have the optional parameters, because otherwise it doesn't reflect correctly in the interface method signature. </p>
  
  <p>Should I skip the optional parameter and just use a nullable type? Or will this work as intended with no side effects or consequences?</p>