{
  ResourceType resource = expression;
  try {
    statement;
  }
  finally {
    ((IDisposable)resource).Dispose();
  }
}

            // First: if the type is a non-nullable value type then we do not do the 
            // *boxing conversion* from the resource to IDisposable. Rather, we do
            // a *constrained virtual call* that elides the boxing if possible. 
            //
            // Now, you might wonder if that is legal; isn't skipping the boxing producing
            // an observable difference?