Re: Default lexical-binding to t

[Alan Mackenzie <acm@muc.de>]

Hello, Eli.

On Thu, Nov 07, 2024 at 08:14:43 +0200, Eli Zaretskii wrote:
> > Date: Wed, 6 Nov 2024 22:50:57 +0000
> > Cc: emacs-devel@gnu.org
> > From: Alan Mackenzie <acm@muc.de>

> > But I do wonder whether the massive time and effort its development
> > and proliferation have taken up were worth it.

> This could be said about almost every major feature in Emacs that
> fundamentally changes the internals.  Are the time, energy, and
> massive efforts I invested (and am still investing) in bidirectional
> editing support worth it?  I don't know; there are days when I think
> it was all a terrible waste.  What about all the multiple changes in
> the internals that bring us 3.7% speedup in some benchmark?  What
> about support for Lisp threads?  What about the addition of positions
> to symbols? in how many error-message situations is this really
> important?  And XInput2, and touch devices, etc. etc.

No, the difference is that most major features are implemented by one
person (or a small team) and are complete in themselves.  Lexical
binding involved significant effort from lots and lots of contributors,
each having to modify "his own" files as lexical binding steadily
morphed from being optional to being compulsory.

I still wonder who made the decision to convert the entire code base,
and when.  Lexical binding, I believe, was first implemented by Miles
Bader, 20 or 25 years ago.  Maybe Gerd, maybe Richard made the decision.
Or maybe nobody made the decision, and the conversion became autonomous,
moving ahead with its own momentum, with nobody really in charge.

> Emacs moves forward because someone whom we trust to be an expert in
> some area or to understand well enough what our users might want has
> an itch to scratch, not because we have some magic future insight.
> Hindsight is always 20-20, but it is also unfair, given our
> development model and the pull of core developers and expertise that
> we can command.

I can't remember any discussion of the technical merits and demerits of
lexical binding taking place on this list.  I've been subscribed for
over 20 years.  Maybe I missed it.  It seems strange, that's all.

-- 
Alan Mackenzie (Nuremberg, Germany).