compatibility problem of whitespace-mode & PrettyControlL?

[Xah Lee]

there seems to be a compatibility problem with whitespace-mode and
both
http://user42.tuxfamily.org/formfeed-hline/index.html and
http://www.emacswiki.org/emacs/PrettyControlL

in short, when one of PrettyControlL or formfeed-hline-mode is loaded,
then the unicode in whitespace-mode disappears.

here's the steps. put the following in your .emacs:

(require 'pp-c-l)
(setq pp^L-^L-string
" ")
(pretty-control-l-mode 1)

;; Make whitespace-mode with very basic background coloring for
whitespaces
(setq whitespace-style (quote ( spaces tabs newline space-mark tab-
mark newline-mark )))
;; Make whitespace-mode and whitespace-newline-mode use “¶” for end of
line char and ▷ for tab.
(setq
whitespace-display-mappings
'(
(space-mark 32 [183] [46]) ; normal space, MIDDLE DOT, FULL STOP.
(space-mark 160 [164] [95])
(space-mark 2208 [2212] [95])
(space-mark 2336 [2340] [95])
(space-mark 3616 [3620] [95])
(space-mark 3872 [3876] [95])
(newline-mark 10 [182 10]) ; newlne
(tab-mark 9 [9655 9] [92 9]) ; tab
))

this should make it look like this (second screenshot):
http://xahlee.org/emacs/whitespace-mode.html

however, it seems when pretty print is loaded, all those triangle and
middle dot doesn't show.

same problem happens with formfeed-hline.

any idea what's going on?

Xah

[Drew Adams]

> there seems to be a compatibility problem with whitespace-mode and
> both http://user42.tuxfamily.org/formfeed-hline/index.html and
> http://www.emacswiki.org/emacs/PrettyControlL
> in short, when one of PrettyControlL or formfeed-hline-mode is loaded,
> then the unicode in whitespace-mode disappears.

...

> it seems when pretty print is loaded, all those triangle and
> middle dot doesn't show. same problem happens with formfeed-hline.
> any idea what's going on?

I replied to your question on Emacs Wiki
(http://www.emacswiki.org/emacs/PrettyControlL). I don't know what causes the
problem, but I can confirm it. Perhaps someone else can help? Sorry.

[Xah Lee]

Thanks Drew.

I found that this problem is reproducible without my personal settings
on whitespace-mode and pretty-control-l-mode.

New steps to reproduce:

(1) load pretty control mode. (require 'pp-c-l)
(2) turn it on. (pretty-control-l-mode 1)
(3) turn on global-whitespace-mode
(4) now the unicode char ( “·”, middle dot, #xb7) used to indicate
spaces are gone.

Some other interesting findings.

• turning off pretty-control-l-mode doesn't help.
• unloading it doesn't fix it neither. (unload-feature 'pp-c-l)
• the problem does not happen if you simply load pp-c-l but doesn't
turn it on. Once turned on, the problem happens and cannot be fixed by
turning off pp-c-l or unloading it.

The above are tested with pp-c-l but it happens with
http://user42.tuxfamily.org/formfeed-hline/index.html
too as i tested earlier.

Xah