Is there any reason for Xcode not to display certain macros and enumeration values in certain classes? In an Objective-C project, the header file of an NSObject class contains some macros and enumerations. These are recognised and work well across the project, and even appear in the auto-complete window when editing other view controller classes. However, in the implementation file of the NSObject class itself, the auto-complete window does not show these macros and enumerations. It still works though, but it's just not seen in auto-complete. The header file is being properly imported. Any ideas what may be causing this?