swap method
Swaps the elements in the indices provided.
var list = [1, 2, 3, 4];
list.swap(0, 2); // [3, 2, 1, 4]
Implementation
void swap(int indexA, int indexB) {
final temp = this[indexA];
this[indexA] = this[indexB];
this[indexB] = temp;
}