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From: "Bruno Félix Rezende Ribeiro" <oitofelix@gnu.org>
To: help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Checking in Lisp if a given symbol has its original value
Date: Tue, 31 Mar 2020 05:14:44 -0300	[thread overview]
Message-ID: <87eet9c557.fsf@oitofelix.com> (raw)

What’s the canonical way of checking if a given symbol has its
original value, as reported by ‘describe-variable’?

I’ve come up with:

#+BEGIN_SRC elisp
  (defun standard-value-p (symbol)
    "Return non-nil if SYMBOL has its original value."
      (equal (eval (car (get symbol 'standard-value)))
             symbol))
#+END_SRC

-- 
Bruno Félix Rezende Ribeiro (oitofelix) [0x28D618AF]
<http://oitofelix.freeshell.org/>



             reply	other threads:[~2020-03-31  8:14 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-31  8:14 Bruno Félix Rezende Ribeiro [this message]
2020-03-31 15:36 ` Checking in Lisp if a given symbol has its original value Drew Adams

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