code: public function filter(callable $condition)
      {
          $items = [];
  
          foreach ($this->items as $item) {
              if ($condition($item)) {
                  $items[] = $item;
              }
          }
  
          $col = new static($this->type);
          $col->setItemsFromTrustedSource($items);
  
          return $col;
      }
docs: {@inheritdoc}