() Bastien <bzg@altern.org>
() Thu, 23 Jan 2014 08:22:17 +0100

   http://bzg.fr/emacs-strip-tease.html

You can use ‘rotatef’ to swap the values of two variables.

(defvar stashed-mode-line-format nil
  "Storage for `toggle-mode-line'.")

(defun toggle-mode-line ()
  "Toggle visibility of mode line."
  (interactive)
  (rotatef mode-line-format
           stashed-mode-line-format))
  
I don't know if this works w/ ‘defvar-local’ vars, however.

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Thien-Thi Nguyen
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