ItemSome<T> class
class ItemSome<T> extends ItemOption<T> {
final List<T> _vs;
ItemSome(this._vs);
T operator[](int i) => _vs[i];
operator[]=(int i, T v) => _vs[i] = v;
}
Extends
ItemOption<T> > ItemSome<T>
class ItemSome<T> extends ItemOption<T> {
final List<T> _vs;
ItemSome(this._vs);
T operator[](int i) => _vs[i];
operator[]=(int i, T v) => _vs[i] = v;
}
ItemOption<T> > ItemSome<T>