traverseOption<B> method

Option<IList<B>> traverseOption<B>(
  1. Option<B> f(
    1. A a
    )
)

Implementation

Option<IList<B>> traverseOption<B>(Option<B> f(A a)) {
  Option<IList<B>> result = some(nil());
  var current = this;
  while(current._isCons()) {
    final gb = f(current._unsafeHead());
    result = result.fold(none, (a) => gb.fold(none, (h) => some(new Cons(h, a))));
    current = current._unsafeTail();
  }
  return result.map((l) => l.reverse());
}