title: Implement PHP interface such that object instance can be passed as array type argument?
body: <p>In PHP it is possible to specify argument types although they call it type hinting.</p>
  
  <p>I am implementing an interface where one of the functions specifies an array as the argument type:</p>
  
  <pre><code>function myFunction(array $argument){
  }
  </code></pre>
  
  <p>I'd like to define a class, an instance of which can be used as the argument for this function. In other words it would extend ArrayObject or implement ArrayAccess or something along those lines.</p>
  
  <p>Is there a built in interface or abstract class that will work for this? (ArrayObject doesn't)</p>