From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?utf-8?B?xaB0xJtww6FuIE7Em21lYw==?= <stepnem@gmail.com>
Subject: Re: [babel] What is `, (backquote comma)?
Date: Wed, 21 Sep 2011 20:46:18 +0200
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In-Reply-To: <867h51x0d5.fsf@googlemail.com> (Thorsten's message of "Wed, 21
	Sep 2011 19:37:42 +0200")
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To: Thorsten <quintfall@googlemail.com>
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On Wed, 21 Sep 2011 19:37:42 +0200
Thorsten wrote:

> in org-babel-expand-body:scheme (and
> e.g. org-babel-expand-body:emacs-lisp) I encounter something like this:
>
> (lambda (var)  (format "%S" (print `(,(car var) ',(cdr var)))))
>=20=09
> While this part
> `(,(car var) ...)
> is explained in the manual (backquote and unquote), this part
> `(... ',(cdr var))
> is a bit mysterious to me, and I do not find information about
> backquote( ... backquote comma ())
> in the manuals or the web.
>
> Is that Emacs Lisp? What does that mean?

Note it's not "`,", which would indeed be a no-op, but "',", which here
means "evaluate the form after "," and quote the result", IOW, the "'"
is just left there (for the same reason you also get to see the even
more funny-looking "`'," and other variations sometimes). Really nothing
new if you've read the backquote section of the Elisp manual.

--=20
=C5=A0t=C4=9Bp=C3=A1n