struct Foo {
  static func foo(a: () -> Int) {}
  func qux(x: Int, y: () -> Int ) {}
}

func testTrailingClosure() -> String {
  Foo.foo(a: { 1 })
  Foo.bar { print(3); return 1 }
  Foo().qux(x: 1, y: { 1 })
  let _ = Foo().quux(x: 1, y: { 1 })

  [1,2,3]
    .filter({ $0 % 2 == 0 })
    .map({ $0 + 1 })
}