swap method

List<T> swap(
  1. int i,
  2. int j
)

returns a list with two swapped items i first item j second item

Implementation

List<T> swap(int i, int j) {
  final list = this.toList();
  final aux = list[i];
  list[i] = list[j];
  list[j] = aux;
  return list;
}