.emacs.el

;; 関数名表示をトグルする
(defun toggle-which-func-mode ()
  (interactive)
  (if which-function-mode
      (which-function-mode -1)
    (which-function-mode 1))
  (if which-function-mode
      (setq-default header-line-format
                    '(which-function-mode ("" which-func-format)))
    (setq-default header-line-format nil)))
(define-key global-map (kbd "<f9>") 'toggle-which-func-mode)