code: public static function addNamespace($name)
  	{
  		@trigger_error('Using ClassLoader::addNamespace() has been deprecated and will no longer work in Contao 5.0.', E_USER_DEPRECATED);
  
  		if (\in_array($name, self::$namespaces))
  		{
  			return;
  		}
  
  		array_unshift(self::$namespaces, $name);
  	}
docs: Add a new namespace
  
  @param string $name The namespace name
  
  @deprecated Deprecated since Contao 4.2, to be removed in Contao 5.