From: Barry Margolin <barmar@alum.mit.edu>
To: help-gnu-emacs@gnu.org
Subject: Re: never use `eval' (was: Re: How to mapcar or across a list?)
Date: Wed, 15 Jul 2015 20:01:55 -0400 [thread overview]
Message-ID: <barmar-526E2F.20015515072015@88-209-239-213.giganet.hu> (raw)
In-Reply-To: mailman.6982.1437001117.904.help-gnu-emacs@gnu.org
In article <mailman.6982.1437001117.904.help-gnu-emacs@gnu.org>,
Emanuel Berg <embe8573@student.uu.se> wrote:
> "Pascal J. Bourguignon" <pjb@informatimago.com>
> writes:
>
> > It's always a bad idea to use eval, because eval
> > evalutes in the nil environment, not in the local
> > lexical envrionment.
>
> I have used `eval' eight times in my current setup of
> 75 files.
>
> Tho some of this code I wrote several years ago, I'd
> be happy to correct it. Any hints - general or
> specific - are appreciated.
>
> ;; From: http://user.it.uu.se/~embe8573/conf/emacs-init/faces.el
>
> (defun set-color-face (name front &optional bold back)
> (eval `(defvar ,(make-symbol name)))
> (eval `(setq ,(intern name)
> `((t (:foreground ,front
> :background ,back
> :bold ,bold) )))))
(eval `(setq ,<expr> <val>))
can practically always be replaced with:
(setf (symbol-value <expr>) <val>)
--
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
next prev parent reply other threads:[~2015-07-16 0:01 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-15 20:14 How to mapcar or across a list? Marcin Borkowski
2015-07-15 20:42 ` Rasmus
2015-07-15 20:55 ` Marcin Borkowski
2015-07-15 22:21 ` Emanuel Berg
2015-07-15 22:21 ` John Mastro
[not found] ` <mailman.6977.1436998965.904.help-gnu-emacs@gnu.org>
2015-07-15 22:28 ` Pascal J. Bourguignon
2015-07-15 22:36 ` Emanuel Berg
2015-07-15 22:57 ` never use `eval' (was: Re: How to mapcar or across a list?) Emanuel Berg
2015-07-15 23:27 ` John Mastro
2015-07-15 23:57 ` Emanuel Berg
2015-07-16 0:18 ` John Mastro
[not found] ` <mailman.6984.1437004760.904.help-gnu-emacs@gnu.org>
2015-07-16 0:04 ` Barry Margolin
[not found] ` <mailman.6982.1437001117.904.help-gnu-emacs@gnu.org>
2015-07-16 0:01 ` Barry Margolin [this message]
2015-07-16 1:13 ` Emanuel Berg
2015-07-17 0:55 ` Emanuel Berg
[not found] ` <mailman.7027.1437094623.904.help-gnu-emacs@gnu.org>
2015-07-17 1:39 ` never use `eval' Pascal J. Bourguignon
2015-07-17 2:16 ` Emanuel Berg
2015-07-17 8:36 ` Barry Margolin
2015-07-17 8:55 ` Pascal J. Bourguignon
2015-07-16 0:22 ` Pascal J. Bourguignon
2015-07-16 1:11 ` Emanuel Berg
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