code: public function checkReservedCodes()
      {
          $reserved = $this->getReservedCodes();
  
          // First iterate: check all factory
          foreach ($reserved as $factoryClass => $reservedForFactory) {
              // Second iterate: check in each factory
              foreach ($reserved as $checkInFactory => $reservedInCheckFactory) {
                  if ($checkInFactory == $factoryClass) {
                      continue;
                  }
  
                  if ($reservedInCheckFactory[0] >= $reservedForFactory[0] &&
                      $reservedInCheckFactory[0] <= $reservedForFactory[1]
                  ) {
                      throw new \RuntimeException(sprintf(
                          'The reserved codes for factory "%s" [%d - %d] superimposed on "%s" factory [%d - %d].',
                          $checkInFactory,
                          $reservedInCheckFactory[0],
                          $reservedInCheckFactory[1],
                          $factoryClass,
                          $reservedForFactory[0],
                          $reservedForFactory[1]
                      ));
                  }
  
                  if ($reservedInCheckFactory[1] >= $reservedForFactory[0] &&
                      $reservedInCheckFactory[1] <= $reservedForFactory[1]
                  ) {
                      throw new \RuntimeException(sprintf(
                          'The reserved codes for factory "%s" [%d - %d] superimposed on "%s" factory [%d - %d].',
                          $checkInFactory,
                          $reservedInCheckFactory[0],
                          $reservedInCheckFactory[1],
                          $factoryClass,
                          $reservedForFactory[0],
                          $reservedForFactory[1]
                      ));
                  }
              }
          }
      }
docs: Check reserved codes
  
  @throws \Exception