Emacs Lisp: Save narrow-to-region

Emacs has a narrow-to-region command. It lets users make the buffer show only the selected region, as if the entire buffer is just that text. This is convenient when you want to do some editing only in this region. Alt + x widen will make buffer show whole buffer again.

The narrow-to-region is also super useful in elisp code. However, when you command is done, you should return to the narrow region state of the user before the command was called. Emacs lisp provides save-restriction for this purpose.

save-restriction

(save-restriction &rest BODY) Execute BODY, saving and restoring user's narrow-to-region .

;; preserve user's narrow-to-region
;; useful when you want to narrow-to-region in your code to work in just that region
(save-restriction
  (narrow-to-region pos1 pos2)
  ;; lisp code here
)

(info "(elisp) Positions")

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