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* bug#18441: tab bug
@ 2014-09-10  6:55 Mario Valencia
  2014-09-10  7:12 ` Mario Valencia
  0 siblings, 1 reply; 6+ messages in thread
From: Mario Valencia @ 2014-09-10  6:55 UTC (permalink / raw)
  To: 18441

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In a buffer, set tab-width to 6. then insert 5 characters, then a literal
tab character (C-q TAB). Now you have a 7 column tab.

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#18441: tab bug
  2014-09-10  6:55 bug#18441: tab bug Mario Valencia
@ 2014-09-10  7:12 ` Mario Valencia
  2014-09-10  7:42   ` Mario Valencia
  0 siblings, 1 reply; 6+ messages in thread
From: Mario Valencia @ 2014-09-10  7:12 UTC (permalink / raw)
  To: 18441

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sorry, this happens in a text-mode buffer with whitespace-mode on. without
whitespace mode it only occupies one column.

2014-09-10 1:55 GMT-05:00 Mario Valencia <mariovalspi@gmail.com>:

> In a buffer, set tab-width to 6. then insert 5 characters, then a literal
> tab character (C-q TAB). Now you have a 7 column tab.
>

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#18441: tab bug
  2014-09-10  7:12 ` Mario Valencia
@ 2014-09-10  7:42   ` Mario Valencia
  2016-02-18  8:53     ` Marcin Borkowski
  0 siblings, 1 reply; 6+ messages in thread
From: Mario Valencia @ 2014-09-10  7:42 UTC (permalink / raw)
  To: 18441

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well it appears to be a known problem, as commented in the source of
whitespace-mode.

2014-09-10 2:12 GMT-05:00 Mario Valencia <mariovalspi@gmail.com>:

> sorry, this happens in a text-mode buffer with whitespace-mode on. without
> whitespace mode it only occupies one column.
>
> 2014-09-10 1:55 GMT-05:00 Mario Valencia <mariovalspi@gmail.com>:
>
>> In a buffer, set tab-width to 6. then insert 5 characters, then a literal
>> tab character (C-q TAB). Now you have a 7 column tab.
>>
>
>

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#18441: tab bug
  2014-09-10  7:42   ` Mario Valencia
@ 2016-02-18  8:53     ` Marcin Borkowski
  2021-09-04  7:57       ` bug#18441: whitespace-mode sometimes adds column to tab character Lars Ingebrigtsen
  0 siblings, 1 reply; 6+ messages in thread
From: Marcin Borkowski @ 2016-02-18  8:53 UTC (permalink / raw)
  To: Mario Valencia; +Cc: 18441

On 2014-09-10, at 03:42, Mario Valencia <mariovalspi@gmail.com> wrote:

> well it appears to be a known problem, as commented in the source of whitespace-mode. 

To be more precise, the comment Mario meant is probably this part of
definition of `whitespace-display-mappings':

--8<---------------cut here---------------start------------->8---
    ;; WARNING: the mapping below has a problem.
    ;; When a TAB occupies exactly one column, it will display the
    ;; character ?\xBB at that column followed by a TAB which goes to
    ;; the next TAB column.
    ;; If this is a problem for you, please, comment the line below.
    (tab-mark     ?\t    [?» ?\t] [?\\ ?\t])	; tab - right guillemet
--8<---------------cut here---------------end--------------->8---

Does anyone know why the workaround given there is not turned on by
default?  Or maybe it should be made a user option?

Best,

--
mbork


> 2014-09-10 2:12 GMT-05:00 Mario Valencia <mariovalspi@gmail.com>:
>
>
>  sorry, this happens in a text-mode buffer with whitespace-mode on. without whitespace mode it only occupies one column.
>
>  2014-09-10 1:55 GMT-05:00 Mario Valencia <mariovalspi@gmail.com>:
>
>
>  In a buffer, set tab-width to 6. then insert 5 characters, then a literal tab character (C-q TAB). Now you have a 7 column tab.





^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#18441: whitespace-mode sometimes adds column to tab character
  2016-02-18  8:53     ` Marcin Borkowski
@ 2021-09-04  7:57       ` Lars Ingebrigtsen
  2022-05-02  9:48         ` Lars Ingebrigtsen
  0 siblings, 1 reply; 6+ messages in thread
From: Lars Ingebrigtsen @ 2021-09-04  7:57 UTC (permalink / raw)
  To: Marcin Borkowski; +Cc: Mario Valencia, 18441

Marcin Borkowski <mbork@mbork.pl> writes:

>> well it appears to be a known problem, as commented in the source of
>> whitespace-mode.

I can confirm that this bug is still present in Emacs 28.

> To be more precise, the comment Mario meant is probably this part of
> definition of `whitespace-display-mappings':
>
>     ;; WARNING: the mapping below has a problem.
>     ;; When a TAB occupies exactly one column, it will display the
>     ;; character ?\xBB at that column followed by a TAB which goes to
>     ;; the next TAB column.
>     ;; If this is a problem for you, please, comment the line below.
>     (tab-mark     ?\t    [?» ?\t] [?\\ ?\t])	; tab - right guillemet
>
> Does anyone know why the workaround given there is not turned on by
> default?  Or maybe it should be made a user option?

If that mark is removed, then tabs won't be marked specially at all --
only with a background colour, which is presumably not what people want
here...

Looking at the whitespace code, I don't really see any easy way to fix
this -- the buffer display table and tab actions don't match?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no





^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#18441: whitespace-mode sometimes adds column to tab character
  2021-09-04  7:57       ` bug#18441: whitespace-mode sometimes adds column to tab character Lars Ingebrigtsen
@ 2022-05-02  9:48         ` Lars Ingebrigtsen
  0 siblings, 0 replies; 6+ messages in thread
From: Lars Ingebrigtsen @ 2022-05-02  9:48 UTC (permalink / raw)
  To: Marcin Borkowski; +Cc: 18441, Mario Valencia

Lars Ingebrigtsen <larsi@gnus.org> writes:

>> To be more precise, the comment Mario meant is probably this part of
>> definition of `whitespace-display-mappings':

This looks like a duplicate of 18548, so I've now merged the two bug
reports.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no





^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2022-05-02  9:48 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-09-10  6:55 bug#18441: tab bug Mario Valencia
2014-09-10  7:12 ` Mario Valencia
2014-09-10  7:42   ` Mario Valencia
2016-02-18  8:53     ` Marcin Borkowski
2021-09-04  7:57       ` bug#18441: whitespace-mode sometimes adds column to tab character Lars Ingebrigtsen
2022-05-02  9:48         ` Lars Ingebrigtsen

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