Dart truthy extension

main.dart

void main() {
  print((null, null.isTruthy));
  print(('', ''.isTruthy));
  print(('false', 'false'.isTruthy));
  print(('true', 'true'.isTruthy));
  print((0, 0.isTruthy));
  print((1, 1.isTruthy));
  print((false, false.isTruthy));
  print((true, true.isTruthy));
  print(([], [].isTruthy));
  print(([1, 2, 3], [1, 2, 3].isTruthy));
  print(({}, {}.isTruthy));
  print(({1, 2, 3}, {1, 2, 3}.isTruthy));
  print(({'a': 1, 'b': 2}, {'a': 1, 'b': 2}.isTruthy));
}

extension on Object? {
  bool get isTruthy => truthy(this);
}

bool truthy(Object? val) {
  if (val == null) return false;
  if (val is bool) return val;
  if (val is num && val == 0) return false;
  if (val is String && (val == 'false' || val == '')) return false;
  if (val is Iterable && val.isEmpty) return false;
  if (val is Map && val.isEmpty) return false;
  return true;
}