// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart = 2.9

/// @assertion Since the spread is unpacked and its individual elements added to
/// the containing collection, we don't require the spread expression itself to
/// be assignable to the collection's type. For example, this is allowed:
///
///    var numbers = <num>[1, 2, 3];
///    var ints = <int>[...numbers];
///
/// This works because the individual elements in numbers do happen to have the
/// right type even though the list that contains them does not. As long as the
/// spread object is "spreadable" — it implements [Iterable] — there is no
/// static error.
/// @description Checks that static error is thrown if null-aware spread element
/// and set type arguments are incompatible.
/// @author iarkh@unipro.ru


main() {
  List<num> numbers = <num>[1, 2, 3];
  Set<String> set = <String>{...?numbers};
//                               ^
// [analyzer] unspecified
// [cfe] unspecified
 }