fillRange method Null safety

void fillRange (
  1. int start,
  2. int end,
  3. [E fill]

Sets the objects in the range start inclusive to end exclusive to the given fillValue.

The provided range, given by start and end, must be valid. A range from start to end is valid if 0 <= start <= end <= len, where len is this list's length. The range starts at start and has length end - start. An empty range (with end == start) is valid.


 List<int> list = new List(3);
    list.fillRange(0, 2, 1);
    print(list); //  [1, 1, null]

If the element type is not nullable, omitting fillValue or passing null as fillValue will make the fillRange fail.


void fillRange(int start, int end, [E? fill]) {
  // Hoist the case to fail eagerly if the user provides an invalid `null`
  // value (or omits it) when E is a non-nullable type.
  E value = fill as E;
  RangeError.checkValidRange(start, end, this.length);
  for (int i = start; i < end; i++) {
    this[i] = value;