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Re: Lexical vs. dynamic: small examples?


From: Gregory Heytings
Subject: Re: Lexical vs. dynamic: small examples?
Date: Sat, 14 Aug 2021 20:23:35 +0000


(defvar saved-buffer-read-only)
(defun delete-whitespace-at-eol ()
  (interactive)
  (setq saved-buffer-read-only buffer-read-only)
  (setq buffer-read-only nil)
  (save-excursion (replace-regexp " *$" "" nil (point-min) (point-max)))
  (setq buffer-read-only saved-buffer-read-only))

OK, but you don't need to store the old value in a global variable...


Of course you do, you need to restore the original value, which could be either t or nil. But indeed TIMTOWTDI: for this specific example, another way to do it would be to introduce a conditional. In general however variables can hold more than two values, so for didactic purposes the above is much clearer.



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