| // Copyright (c) 2023, 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. |
| |
| void main() { |
| for (var _ in split([1,2,3])) {} |
| } |
| |
| Iterable<(Iterable<A>, Iterable<A>)> split<A>(Iterable<A> it) => switch (it) { |
| Iterable<A>(isEmpty: true) => [(Iterable<A>.empty(), Iterable<A>.empty())], |
| Iterable<A>(first: var x) => () sync* { |
| yield (Iterable<A>.empty(), it); |
| for (var (ls, rs) in split(it.skip(1))) |
| yield ([x, ...ls], rs); |
| }(), |
| }; |
