asMap method
Returns an ImmortalMap using the indices of this list as keys and the corresponding objects as values.
Example:
final words = ImmortalList(['fee', 'fi', 'fo', 'fum']);
final map = words.asMap();
map[0].value + map[1].value; // 'feefi'
map.keys.toList(); // [0, 1, 2, 3]
Implementation
ImmortalMap<int, T> asMap() => ImmortalMap(_list.asMap());