ListSignalMixin is a mixin for a Signal that adds reactive methods for List.
class MySignal extends Signal<List<int>> with ListSignalMixin<int> { MySignal(List<int> value) : super(value);} void main() { final signal = MySignal([1, 2, 3]); effect(() { print(signal.length); }); signal.add(4); signal.remove(1); print(signal.contains(2)); // true}