code: public function in($conditions, $value = false, $comparison = 'IN')
      {
          $val = $value;
          if (!is_array($value)) {
              $val = explode(',', $val);
          }
          $this->store('condition', 'wheres', $conditions, $val, $comparison);
          return $this;
      }
docs: public function in($column, $fields)