private function initTypeGuesser()
    {
        $this->typeGuesserLoaded = true;

        $this->typeGuesser = $this->loadTypeGuesser();
        if (null !== $this->typeGuesser && !$this->typeGuesser instanceof BlockTypeGuesserInterface) {
            throw new UnexpectedTypeException($this->typeGuesser, 'Fxp\Component\Block\BlockTypeGuesserInterface');
        }
    }