Re: treesit indentation "blinking"

[Dmitry Gutov <dgutov@yandex.ru>]

On 04/04/2023 00:59, Daniel Colascione wrote:
> On April 3, 2023 08:07:17 Dmitry Gutov <dgutov@yandex.ru> wrote:
> 
>> On 03/04/2023 12:59, Alan Mackenzie wrote:
>>> Hello, Dmitry.
>>>
>>> On Mon, Apr 03, 2023 at 00:21:18 +0300, Dmitry Gutov wrote:
>>>> On 02/04/2023 20:23, João Távora wrote:
>>>>> So my initial idea was to tone down electric-indent-chars, at least
>>>>> for the moment.  And Dmitry's idea was to make electric-indent-chars
>>>>> be ambitious_only_  if electric-pair-mode is enabled (by the user).
>>>>> Maybe we should bring back that idea, and it seems the least bad of the
>>>>> bunch right now.
>>>
>>>> Alternatively, we only perform "electric indent" (aside from after RET)
>>>> when the parse tree does not contain errors.
>>>
>>> That is NOT electric indentation.  The whole point about electric
>>> indentation is for it to take effect whilst point is still on the line
>>> being edited.  Thus, for example, you can see whether or not the line
>>> needs breaking, or whether there's room for a short comment at the end
>>> of the line.
>>
>> Wouldn't you know whether the line needs breaking, as long as the line
>> was indented correctly when you opened it with RET?
>>
>>> What you're proposing is something which would almost never trigger,
>>> since a line being edited will not have a parse tree without errors (if
>>> I've understood that properly).  If it did trigger at some point, that
>>> would likely cause annoyance and puzzlement.
>>
>> That's a fair assessment, but it's going to trigger in a lot of cases
>> still: after ;, or after a paren or brace being closed.
> 
> Silly question: can't we make a mode with c++-mode's indentation (and 
> folding etc.) and c++-ts-mode's fontification? Such a thing would also 
> preserve compatibility with the numerous ad hoc c++-mode styles out there.

Sure, we could: inherit from c++-mode and add then add most of 
c++-ts-mode's definition, just without indent-related variables. 
python-ts-mode is an example of such mode.

Whatever performance complaints people had about c++-mode, though, those 
will stay around, and perhaps get a little bit worse due to additional 
work of maintaining the tree-sitter parse tree.

And at least some of CC Mode's latest bug reports related to problems 
"parsing" the code (in the way that CC Mode does that). Such problems 
would be harder to spot when using the new hybrid mode because they 
won't affect syntax highlighting, but they could still affect indentation.