title: Why doesn't .Net 4 allow me to pass in an array of an interface?
body: <p>I have an array of Circle objects (where Circle implements IShape interface and i have a function that has a parameter of <code>List&lt;IShape&gt;</code> . . why can't i pass in my array of Circles into this ?</p>
  
  <p>Visual studio gives me a build error saying  can't convert <code>List&lt;Circle&gt;</code> to <code>List&lt;IShape&gt;</code></p>