magic-mode-alist and cc-other-file-list

gistfile1.el

;; load objc-mode for objective-C header files
(add-to-list 'magic-mode-alist
             '((lambda ()
                  (and (string= (file-name-extension buffer-file-name) "h")
                       (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t)))
               . objc-mode))

;;set .m <-> .h correspondence for ff-find-other-file
(add-hook 'objc-mode-hook
          (lambda ()
            (set (make-local-variable 'cc-other-file-alist)  '(("\\.m\\'" (".h")) ("\\.h\\'" (".m" ".c" ".cpp"))))))