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From: Xue Fuqiao <xfq.free@gmail.com>
To: help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Why does `(window-line-height)' return nil?
Date: Sat, 3 Aug 2013 16:26:50 +0800	[thread overview]
Message-ID: <CAAF+z6GcZZ-gGuvYjkK9QP7d7PHSA4Hu22gMX+D_ZjL-doei-w@mail.gmail.com> (raw)

Hi,

In my *scratch* buffer, all of the following expressions return nil with
`eval-print-last-sexp' (also tried `eval-last-sexp'):

--8<---------------cut here---------------start------------->8---
(window-line-height 'header-line)
(window-line-height 'mode-line)
(window-line-height)
(window-line-height 0)
(window-line-height -1)
--8<---------------cut here---------------end--------------->8---

Why do they return nil?  After reading the doc string, I only found one
sentence that may be relavant: "Return nil if window display is not
up-to-date."  So, does that mean window display is not up-to-date when
evaluating the expression?  I've searched the archives/web, but found
little information about this function.

-- 
Best regards, Xue Fuqiao.
http://www.gnu.org/software/emacs/



             reply	other threads:[~2013-08-03  8:26 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-03  8:26 Xue Fuqiao [this message]
2013-08-03  9:01 ` Why does `(window-line-height)' return nil? Eli Zaretskii
2013-08-04  3:52   ` Xue Fuqiao

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