System Headers Changes System Headers /usr/include/objc/runtime.h Added object_isClass() Sending feedback… We’re sorry, an error has occurred. Please try submitting your feedback later. Thank you for providing feedback! Your input helps improve our developer documentation. How helpful is this document? * Very helpful Somewhat helpful Not helpful How can we improve this document? Fix typos or links Fix incorrect information Add or update code samples Add or update illustrations Add information about... * * Required information To submit a product bug or enhancement request, please visit the Bug Reporter page. Please read Apple's Unsolicited Idea Submission Policy before you send us your feedback.