toList method
- bool growable = true,
 
override
    Creates a List containing the elements of this Iterable.
The elements are in iteration order.
The list is fixed-length if growable is false.
Example:
final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Mars'};
final keysList = planets.keys.toList(growable: false); // [1, 2, 3]
final valuesList =
    planets.values.toList(growable: false); // [Mercury, Venus, Mars]
Implementation
@override
List<E> toList({bool growable = true}) {
  if (isEmpty) {
    return List<E>.empty(growable: growable);
  }
  final list = List<E>.filled(length, elementAt(0), growable: growable);
  for (var i = 1; i < length; i++) {
    list[i] = elementAt(i);
  }
  return list;
}