Re: Status update of tree-sitter features

[Dmitry Gutov <dgutov@yandex.ru>]

On 29/12/2022 02:23, Yuan Fu wrote:

>>> function                every function identifier
>>
>> The description makes it easy to mistake for function definitions as well. Whereas the place where this category is used is function/method calls, right? And perhaps some other references to methods inside the code where the language parser can distinguish those from property access, etc.
>>
>> If it's only about calls, maybe call this category funcall?
> 
> Function, property and variable are for every occurrence of them (the touted “consistent highlighting”). So there will be a bit of overlap between function, variable, and definition.

By "overlap", do you mean that font-lock rules should also have entries 
for variable/function definitions with category 'variable'/'function'?

In case somebody removes 'definition' from their list of enabled 
features but keeps 'variable' and 'function' there?

>>> variable                every variable identifier
>>
>> 'variable', so far, seems like the least useful. When enabled, it lights up every bit of text that remained from other matchers -- because identifier are everywhere.
> 
> Yes, but apparently people want it ;-)

Well, if they really do.

I figured that people who added this maybe haven't tested this 
thoroughly. And that maybe they expected the effect of that "local 
variables highlights" feature that some editors showcase already.

>> There is this more advanced prior art for highlighting variables, by tracking the scopes using custom annotations, see locals.scm here:
>>
>> https://tree-sitter.github.io/tree-sitter/syntax-highlighting#local-variables
>>
>> What's displayed under "Result" would be really handy to have in Ruby.
>>
>> It's nothing urgent, of course. Maybe for Emacs 30?
> 
> Yeah, this requires some non-trivial addition to the current fontification code.

Thank you.

>> For Emacs 29, though, I would discourage the use of 'variable’.
> 
> It’s on level 4, meaning not enabled by default, so I think it’s fine.

Fair enough. If someone wants function/property but not variable, they 
could fine-tune the list.