Re: Tree-sitter integration on feature/tree-sitter

[Yuan Fu]

> On May 10, 2022, at 12:58 PM, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
> 
>> Eli/Stefan, please guide us!
> 
> I don't have much to say.  OK, let's invent something:
> 
> 1- Maybe it would be good to expose "compiled query" objects to ELisp,
>   so the compilation could be performed by explicit requests (so you
>   don't have to cache it, instead the major modes would call the
>   function when installing their indentation/fontlock rules).

Maybe something like (treesit-cache-query key query), that saves exposing 
another type to lisp.


> 
> 2- I don't understand why the use of hash map is perceived as complex.
>   It seems like a fairly simple solution.

I’m not sure how would we garbage collect unused queries, maybe I’m missing 
something. And is there a C hash table that we can use? Or we need to use the 
lisp hash table? 

Maybe we can use a buffer-local treesit--query-cache hash table and store 
USERPTR of TSQuery in it, so we don’t worry about garbage collecting. Would 
that be slow (getting the buffer-local variable, do a lookup, takeout the 
TSQuery object)?

Yuan