code: public function getResolvedConcreteFlag($abstract)
      {
          if (!$this->hasResolvedConcrete($abstract)) {
              throw Internal\Exception\ReflectionExceptionFactory::invalidArgument(
                  sprintf(
                      "Parameter 1 of %s must be an abstract class name which exists in resolved concrete stack.",
                       __METHOD__
                  )
              );
          }
  
          return explode('|', $this->resolved[$abstract]['flag']);
      }
docs: Get flag of resolved concrete behavior on abstract class name.
  
  @param string $abstract The resolved abstract class name.