🅵
Ну и всо, ответ:
// ignore_for_file: avoid_print
void main() =>
print(const <Object>[7,5,3,5,'a',8,2,6,'a',1,5,2]
.fold<List<List<int>>>(<List<int>>[<int>[]],
(List<List<int>> list, Object element) =>
(element is int)
? (list..last.add(element))
: (list..add(<int>[]))
));