bug#67207: [PATCH] Add elixir-ts-mode-hook to elixir-ts-mode

[Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

>>> Stefan, does this mean define-derived-mode has some deficiency?
>>> Many/most modes defined using it don't have an explicit hook
>>> definition, so should we now define a mode hook for all of them?
>> Usually we don't have good ideas of `:options` to provide for hook
>> variables, so it's not very useful to expose them to Custom.
> After I had a look how it works, it seems pretty convenient for users
> relying on customize menus and not knowing which hooks might be useful.
> There are some modes using this feature, but its not consistently used.

Yes but it's unreliable: as soon as some code uses `add-hook` on this
hook variable, Custom gets all confused because it doesn't know
why/where the variable has a different value from the one it expected.

> Won't it make sense to define a hook to custom anyways, so that users
> get used to the idea of using the customize menus to add hooks?

As long as Custom breaks down when someone uses `add-hook`, I don't feel
comfortable exposing unsuspecting users to the brittleness of hooks in
Custom :-(

Custom's main audience is specifically those users who don't (want to) know
about such tricky interactions.

> Only after using Emacs for 5+ years now I am only now discovering the
> convenience of the customize menu, probably getting too lazy to update
> init.el.

:-)


        Stefan