src/StatedClass/LifeCyclableTrait.php
public function unregisterObserver(ObservedInterface $observed): LifeCyclableInterface
    {
        $observedHash = \spl_object_hash($observed);

        if (isset($this->observedList[$observedHash])) {
            unset($this->observedList[$observedHash]);
        }

        return $this;
    }
public function unregisterObserver(ObservedInterface $observed): LifeCyclableInterface
    {
        $observedHash = \spl_object_hash($observed);

        if (isset($this->observedList[$observedHash])) {
            unset($this->observedList[$observedHash]);
        }

        return $this;
    }
To unregister a previous registered observer.

@param ObservedInterface $observed

@return LifeCyclableInterface