May something wrong with concealcursor.

[yangxyo]

I want to hide the char of the first-level tab.

set listchars=tab:\¦\ ,trail:■,extends:>,precedes:<,nbsp:+
set list
hi SpecialKey ctermfg=239 ctermbg=202

set conceallevel=1
set concealcursor=inc
call matchadd('Conceal', '^\t', 0, -1, {'conceal':'	'})
hi Conceal ctermfg=NONE ctermbg=NONE

VIM - Vi IMproved 8.2
MacOS 10.15.5 

I don't know whether it is a bug. So I created a blank one.

[k-takata]

Could you explain what is your expected behavior?

[yangxyo]

set listchars=tab:\¦\ ,trail:■,extends:>,precedes:<,nbsp:+
set list
hi SpecialKey ctermfg=239 ctermbg=202

It started like this:

But I woloud like this(Do not show the first-level tab char):

So I add:

set conceallevel=1
set concealcursor=inc
call matchadd('Conceal', '^\t', 0, -1, {'conceal':'	'})
hi Conceal ctermfg=NONE ctermbg=NONE

But actually show(When I move the cursor the indent will change, it's strange):

[yangxyo]

Could you explain what is your expected behavior?

Is there any way to solve it？

[chrisbra]

While I think this is already stretching what an editor should do a bit too much by using concealing and listchars, it looks like a bug. I see rendering issues on the line where the cursor is (displaying different characters). In addition, it looks like the concealing code does not handle using a tab as a conceal character very well.

[chrisbra]

reproduced with 8.2.1114 using the following snippet:

set listchars=tab:\¦\ ,trail:■,extends:>,precedes:<,nbsp:+
set list ts=8
hi SpecialKey ctermfg=239 ctermbg=202
set conceallevel=1
set concealcursor=inc
call matchadd('Conceal', '^\t', 0, -1, {'conceal':"\t"})
hi Conceal ctermfg=NONE ctermbg=NONE

	"foobar eins 	zwei
	"foobar eins 	zwei
	"foobar eins 	zwei

Note how the line where the cursor is is rendered differently (wrong). See commandline for the actual content.

[k-takata]

:help matchadd() says:

			conceal	    Special character to show instead of the
				    match (only for |hl-Conceal| highlighted
				    matches, see |:syn-cchar|)

and :help :syn-cchar says:

The character cannot be a control character such as Tab.

So, this is a limitation?

[chrisbra]

Oh yes, indeed. I remember having read this in the past, but missed it.

[yangxyo]

and :help :syn-cchar says:

The character cannot be a control character such as Tab.

So, this is a limitation?

Because of this, I use {'conceal':' '}), rather than {'conceal':' \t'})
And I do realize it.
As the second image:
#6375 (comment)
However, as the third image, when my cursor passes the line, it crashes.

[chrisbra]

Because of this, I use {'conceal':' '}), rather than {'conceal':' \t'})

That was not in your original issue. It contained a literal tab, I just converted it to use \t instead.

However, as the third image, when my cursor passes the line, it crash.

What do you mean here? Can you post a backtrace please?

[yangxyo]

[yangxyo]

It seems set concealcursor=inc, its performance doesn't like the help: concealcursor.

[yangxyo]

😂But，in fact, I don't want to feedback bug, I'm looking for the way to "hide the character of the first-level tab".

[yangxyo]

It not only the indent unusual, but it also completes collapse.

I only type the "j->o -> fo -> dd -> dsfaf->k"

[yangxyo]

@chrisbra

Because of this, I use {'conceal':' '}), rather than {'conceal':' \t'})

That was not in your original issue. It contained a literal tab, I just converted it to use \t instead.

I first don't think: {'conceal':' '} == {'conceal':' \t'} , so I use {'conceal':' '} 😂.

However, I still think it is sth. wrong because it worked first, it is that the set concealcursor=inc does not work as far as I see, hah.

And I only need sth. to replace or hide the ¦ of '^\t'. However, I don't allow to use four spaces , because it is cstr that can't be used for matchadd of Vim now, it will be analyzed to one space.

[yangxyo]

@chrisbra

While I think this is already stretching what an editor should do a bit too much by using concealing and listchars

Is there a way toset listchars =tab:\ \ for the first-level tab, while set listchars =tab:\¦\ for others?

[chrisbra]

Is there a way toset listchars =tab:\ \ for the first-level tab, while set listchars =tab:\¦\ for others?

No, listchars is intended to be used for all characters that follow. Perhaps you should try to explain, what actual problem you are trying to solve. I must confess, I couldn't follow your messages and it is not clear to me what you want to achieve and why.

[yangxyo]

I'm so sorry.

What actual problem you are trying to solve

I need the Indent alignment lines.

set listchars=tab:\¦\ ,trail:■,extends:>,precedes:<,nbsp:+
set list
hi SpecialKey ctermfg=239 ctermbg=202

It started like this:

But I would like this which does not display the first-level tab character:

Why

I think It will be more reasonable, simple, and beautiful. "Radish or cabbage; each to his own delight."
I hope I explained it clearly.🌚