Re: Emacs rewrite in a maintainable language

[David Kastrup <dak@gnu.org>]

Oleh Krehel <ohwoeowho@gmail.com> writes:

> Óscar Fuentes <ofv@wanadoo.es> writes:
>
>> Replacing C with a language that helps people to write readable,
>> safe, efficient and maintainable code without having to study the
>> existing code base for months looks quite appealing to me. That
>> replacement could be gradual (no "stopping the world while The Big
>> Rewrite is underway.")  If that language is not so popular as C,
>> that's no big problem as long as it makes things less daunting for
>> those willing to work on the Emacs core. As already said, there is no
>> dramatic shortage of people who learn Elisp just for hacking Emacs.
>
> I think slowly moving the Emacs C core to C++ is a good idea.

I don't, and the reasons are similar to why Linux on C++ crashed and
burned.

The theory is very nice, but C++ is not a stable basis.  Every 5 years
it gets completely redefined, and the Elisp semantics don't magically
move with that.

> I've been trying to get into understanding Emacs C core, but it's just
> so hard with all those macros around. I think even replacing `#define`
> with `const` would be a huge improvement, worthwhile of the switch.
> The second step would be to replace some macros with type checked
> template functions.

"template functions"?  Seriously?  Template mechanisms are compile-time
mechanisms.  They would not correspond to anything in Elisp, ever.  So
they'd end up in parallel construction, with a construction on the C++
side of things that the C++ standard committee changes around every 5
years.

-- 
David Kastrup