Dart Iterable.where and Iterable.map lazyness test

main.dart

void main() {
  final data = new List.generate(100, (i) => i);
  final result = data.where((i) {
    print('where $i');
    return i > 0 && i % 10 == 0;
  }).map((i) {
    print('map $i');
    return i / 10;
  });
  print('==========');
  print(result.first);
}