sumOf method

num sumOf(num selector(num element))

Returns the sum of all values produced by selector function applied to each element in the collection.

Implementation

num sumOf(num Function(num element) selector) {
  if (isEmpty) return 0;

  final iterator = this.iterator..moveNext();
  var sum = selector(iterator.current);

  while (iterator.moveNext()) {
    sum += selector(iterator.current);
  }

  return sum;
}