e to generate a new instance even if the class was registered as shared.
	 *
	 * @return object An instance of the requested class.
	 * @throws ContainerException Attempt to get an instance of a non-namespaced class.
	 */
	public function get( $id, bool $new = false ) {
		if ( false === strpos( $id, '\\' ) ) {
			throw new ContainerException( "Attempt to get an instance of the non-namespaced class '$id' from the container, did you forget to add a namespace import?" );
		}

		return parent::get( $id, $new );
	}

	/**
	 * Gets the class from the concrete regardless of type.
	 *
	 * @param mixed $concrete The concrete that we want the class from..
	 *
	 * @return string|null The class from the concrete if one is available, null otherwise.
	 */
	protected function get_class_from_concrete( $concrete ) {
		if ( is_object( $concrete ) && ! is_callable( $concrete ) ) {
			if ( $concrete instanceof DefinitionInterface ) {
				return $this->get_class_from_concrete( $concrete->getConcrete() );
			}

			return get_class( $concrete );
		}

		if ( is_string( $concrete ) && class_exists( $concrete ) ) {
			return $concrete;
		}

		return null;
	}

	/**
	 * Checks to see whether or not a class is allowed to be registered.
	 *
	 * @param string $class_name The class to check.
	 *
	 * @return bool True if the class is allowed to be registered, false otherwise.
	 */
	protected function is_class_allowed( string $class_name ): bool {
		return StringUtil::starts_with( $class_name, $this->woocommerce_namespace, false ) || in_array( $class_name, $this->registration_whitelist, true );
	}
}