var i = 1;

Map<int, String>? nullableMap = {1: "Let", 2: "it", 3: "be"};

List<int>? nullableList = [1, 2, 3];

dynamic dynamicMap = {1: "Let", 2: "it", 3: "be"};

dynamic dynamicList = [1, 2, 3];

var map1 = {
  if (i > 0) ...nullableMap,
  if (i > 0) ...dynamicMap,
  if (i > 0) ...nullableMap!,
};

var set1 = {
  0,
  if (i > 0) ...nullableList,
  if (i > 0) ...dynamicList,
  if (i > 0) ...nullableList!
};

var list1 = [
  if (i > 0) ...nullableList,
  if (i > 0) ...dynamicList,
  if (i > 0) ...nullableList!,
];

testMap<X extends dynamic, Y extends Map<int, String>?,
    Z extends Map<int, String>>(X x, Y y, Z z) {}

testIterables<X extends dynamic, Y extends List<int>?, Z extends List<int>>(
    X x, Y y, Z z) {}

main() {}