bind<B> method

@override IList<B> bind<B>(covariant Function1<A, IList<B>> f)

Implementation

@override IList<B> bind<B>(Function1<A, IList<B>> f) {
  final IList<B> bNil = nil();
  if (!_isCons()) {
    return bNil;
  }
  Cons<B>? result = null;
  IList<B>? resultHead = null;
  var current = this;
  var sub = f(current._unsafeHead());
  while(current._isCons() && !sub._isCons()) {
    current = current._unsafeTail();
    if (current._isCons()) {
      sub = f(current._unsafeHead());
    }
  }
  if (sub._isCons()) {
    result = new Cons(sub._unsafeHead(), bNil);
    resultHead = result;
    sub = sub._unsafeTail();
    while(sub._isCons()) {
      final next = new Cons(sub._unsafeHead(), bNil);
      result!._unsafeSetTail(next);
      result = next;
      sub = sub._unsafeTail();
    }
    current = current._unsafeTail();
  }
  while (current._isCons()) {
    sub = f(current._unsafeHead());
    while(sub._isCons()) {
      final next = new Cons(sub._unsafeHead(), bNil);
      result!._unsafeSetTail(next);
      result = next;
      sub = sub._unsafeTail();
    }
    current = current._unsafeTail();
  }
  return resultHead ?? bNil;
}