>>>
import "package:expect/expect.dart";
int Function() x = () => 42;
int Function(int Function()) y = (int Function() x) => x();
List<int Function()> l = <int Function()>[()=>42, x];
main() {
  Expect.equals(42, y(l[1]));
}
<<<
import "package:expect/expect.dart";

int Function() x = () => 42;
int Function(int Function()) y = (int Function() x) => x();
List<int Function()> l = <int Function()>[() => 42, x];
main() {
  Expect.equals(42, y(l[1]));
}