core-bundle/src/Resources/contao/library/Contao/Model/Registry.php
public function isRegistered(Model $objModel)
	{
		$intObjectId = spl_object_hash($objModel);

		return isset($this->arrIdentities[$intObjectId]);
	}
public function isRegistered(Model $objModel)
	{
		$intObjectId = spl_object_hash($objModel);

		return isset($this->arrIdentities[$intObjectId]);
	}
Check if a model is registered

@param Model $objModel The model object

@return boolean True if the model is registered