struct S1 { x : int; y : int; }
struct S2 { x : int; y : int; }

class C
{ 
  public static Main () : void
  {
    _ = S1 () :> S2; // E: cannot convert S1 to S2

    // bug #688
    def a = array [1,2] : array[int];
    _ = a :> array [string]; // E: cannot convert array\[int\] to array\[string\]

    def a = array[S1()];
    _ = a :> array[S2]; // E: cannot convert array\[S1-\] to array\[S2\]
  }

  public static foo () : void
  {
    _ = "string" :> string; // W: there is no check needed to cast string to string
  }
}