Subject: bug#22303: closed (Re: bug#22303: 24.5; toggle-truncate-lines not mentioned in docstring for truncate-lines nor in elisp manual)

From: [email-masked] (GNU bug Tracking System)
Date: Mon, 04 Jan 2016 17:12:02 +0000

Your bug report

#22303: 24.5; toggle-truncate-lines not mentioned in docstring for truncate-lines nor in elisp manual

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
22303: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=22303
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#22303: 24.5; toggle-truncate-lines not mentioned in docstring for truncate-lines nor in elisp manual
From: Eli Zaretskii <[email-masked]>
To: [email-masked]
Cc: [email-masked]
Date: Mon, 04 Jan 2016 19:11:31 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

> From: phs <[email-masked]>
> Date: Mon, 4 Jan 2016 10:30:17 +0100
> 
> In general, changing the value of `truncate-lines' should be done via 
> `toggle-truncate-lines' not by `(setq truncate-lines ..)'
> 
> However the documentation string for `truncate-lines' does not mention 
> the existence of `toggle-truncate-lines', nor is it mentioned in the
> elisp manual (section "37.3 Truncation").
> 
> It seems that modifying `truncate-lines' with just `(setq ..)' may 
> suffer from redisplay problems, see 
> http://emacs.stackexchange.com/questions/19228 for a way to trip the 
> problem from emacs -Q.

Thanks for pointing this out.

The answers on stackexchange are incorrect: there's nothing wrong with
setting 'truncate-lines' directly.  The situation described there
revealed a bug, which I just fixed for the next release.

I see no need to change the documentation in this regard.

Subject: 24.5; toggle-truncate-lines not mentioned in docstring for truncate-lines nor in elisp manual
From: phs <[email-masked]>
To: [email-masked]
Date: Mon, 4 Jan 2016 10:30:17 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

In general, changing the value of `truncate-lines' should be done via 
`toggle-truncate-lines' not by `(setq truncate-lines ..)'

However the documentation string for `truncate-lines' does not mention 
the existence of `toggle-truncate-lines', nor is it mentioned in the
elisp manual (section "37.3 Truncation").

It seems that modifying `truncate-lines' with just `(setq ..)' may 
suffer from redisplay problems, see 
http://emacs.stackexchange.com/questions/19228 for a way to trip the 
problem from emacs -Q.

--phs

In GNU Emacs 24.5.1 (x86_64-apple-darwin13.4.0, NS apple-appkit-1265.21)
  of 2015-04-10 on builder10-9.porkrind.org
Windowing system distributor `Apple', version 10.3.1404
Configured using:
  `configure --with-ns '--enable-locallisppath=/Library/Application
  Support/Emacs/${version}/site-lisp:/Library/Application 
Support/Emacs/site-lisp''

Important settings:
   value of $LC_ALL: en_US
   value of $LANG: en_US
   locale-coding-system: utf-8-unix

-- 
Philippe SCHNOEBELEN,       	                  www.lsv.ens-cachan.fr/~phs
LSV, CNRS UMR 8643 & ENS de Cachan   		  Tel: (+33/0) 147 407 530
"Algebraic symbols are used when you do not know what you are talking about"