Switching between header and source file in objective-C

objc-mode-config.el

(defun objc-in-header-file ()
  (let* ((filename (buffer-file-name))
         (extension (car (last (split-string filename "\\.")))))
    (string= "h" extension)))

(defun objc-jump-to-extension (extension)
  (let* ((filename (buffer-file-name))
         (file-components (append (butlast (split-string filename
                                                         "\\."))
                                  (list extension))))
    (find-file (mapconcat 'identity file-components "."))))

;;; Assumes that Header and Source file are in same directory
(defun objc-jump-between-header-source ()
  (interactive)
  (if (objc-in-header-file)
      (objc-jump-to-extension "m")
    (objc-jump-to-extension "h")))

(defun objc-mode-customizations ()
  (define-key objc-mode-map (kbd "C-c t") 'objc-jump-between-header-source))

(add-hook 'objc-mode-hook 'objc-mode-customizations)