From: Wilhelm Kirschbaum <wkirschbaum@gmail.com>
Cc: 60453@debbugs.gnu.org
Date: Sat, 31 Dec 2022 18:50:31 +0200
Eli Zaretskii <eliz@gnu.org> writes:
>> From: Wilhelm Kirschbaum <wkirschbaum@gmail.com>
>> Date: Sat, 31 Dec 2022 16:53:08 +0200
>>
>>
>> With the following code without tree-sitter library:
>>
>> (defvar elixir-ts-mode--treesit-range-rules
>> (treesit-range-rules
>> :embed 'heex
>> :host 'elixir
>> '((sigil (sigil_name) @name (:match "^[H]$" @name)
>> (quoted_content)
>> @heex))))
>>
>> upon loading the mode I get the following error:
>>
>> treesit-range-rules: Symbol’s function definition is void:
>> treesit-query-compile
>>
>> This can easily be mitigated with (when
>> (treesit-available-p)...)
>> but think it should function similar to how
>> (treesit-font-lock-rules
>> work.
>
> Why does it make sense to protect treesit.el's code with
> treesit-available-p? You aren't supposed to use treesit.el
> functions
> when the tree-sitter library is not available. IOW, Lisp
> programs
> that want to use treesit-range-rules and other functions from
> treesit.el should make the treesit-available-p test _before_
> that.
Okay, that makes sense. I just saw this comment on
;; treesit.el#618
(defun treesit-font-lock-rules (&rest query-specs)
...
;; Other tree-sitter function don't tend to be called unless
;; tree-sitter is enabled, which means tree-sitter must be
compiled.
;; But this function is usually call in `defvar' which runs
;; regardless whether tree-sitter is enabled. So we need
this
;; guard.
(when (treesit-available-p)
As treesit-range-rules also gets called with defvar and it is a
consistency issue. I think the reason why this has not popped
up
before is that no other modes I have seen uses
treesit-range-rules
yet and think it will probably catch people off guard in the
future.