void removeRange(int start, int end)

Removes the objects in the range start inclusive to end exclusive.

The provide 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.

Throws an UnsupportedError if this is a fixed-length list. In that case the list is not modified.

Source

void removeRange(int start, int end) {
  RangeError.checkValidRange(start, end, this.length);
  int length = end - start;
  setRange(start, this.length - length, this, end);
  this.length -= length;
}