Drifting towards a statically typed Emacs Lisp. [Was: Introducing 'safety' compilation parameter]

[Alan Mackenzie]

Hello, Eli.

On Tue, May 07, 2024 at 16:15:47 +0300, Eli Zaretskii wrote:
> > Date: Tue, 7 May 2024 12:01:33 +0000
> > Cc: emacs-devel@gnu.org, Eli Zaretskii <eliz@gnu.org>,
> >   monnier@iro.umontreal.ca, mattias.engdegard@gmail.com,
> >   stefankangas@gmail.com
> > From: Alan Mackenzie <acm@muc.de>

> > I see this change as one more boil-the-frog-slowly step towards turning
> > Emacs Lisp into a statically typed language.

> Alan, please be kinder, even if you dislike very much suggestions of
> others.

No offence was intended.

> The above could have been easily rephrased as

>   Emacs Lisp should not be turned into a statically typed language.

> without losing any useful content, ....

Not really - what would have been lost is the equivalent  of ".... and I
see this process happening at the moment.".  The frog metaphor was an
economical way of phrasing this.  Again, I'm sorry it caused offence.

> .... including your strenuous objection to the change.

I see Emacs Lisp steadily drifting towards being statically typed, and I
don't think that's a good thing.  As far as I'm aware, there has been no
general agreement amongst Emacs developers for this (unless it's
happened as a side-thread in some thread without having an accurate
Subject:).

We currently have the prospect of lots of functions being cluttered up
with "type" declarations.  We already have meaningless (to a Lisp
programmer) things like:

    Inferred type: (function (&optional t t) t)                                 
                                           

appearing in prominent positions in doc strings.  Why?

If this is the way Emacs Lisp is to develop, can't we at least have an
open discussion about it and a positive decision taken, rather than
letting it "just happen"?  As is already clear, I see static typing in
Emacs Lisp, except, perhaps, on a very limited scale, as a Bad Thing.

-- 
Alan Mackenzie (Nuremberg, Germany).