Re: The Case for Rust (in the base system)

From: Bertrand Petit <freebsd-hackers_at_phoe.frmug.org>
Date: Sun, 21 Jan 2024 10:24:21 UTC
On Sun, Jan 21, 2024 at 07:51:32AM +0000, Poul-Henning Kamp wrote:
> 
> I also propose, that next time somebody advocates for importing
> some "all the cool kids are doing it language" or other, we refuse
> to even look at their proposal, until they have proven their skill
> in, and dedication to, the language, by faithfully reimplementing
> cvsup in it, and documented how and why it is a better language for
> that, than Modula-3 was.

	That is probably quite tough a measure but I understand and like your
point. I also would also love to read the kool kids explain why the blunt
assertion that "<something> can't be implemented unless written in rust" is
true as this seems to be contrary to all I know about computer science. (They
probably never heard of haskell.)

	That asside, as much as I would like to see erlang and zig in base
(yes, I like type systems), I would never advocate for them to be considered.
I find these languages as well as rust so different in their environments,
runtime and ecosystems, that their integration would require a so heavy
shoehorning that it would probably result in a value less than the sum of them
all.

	One of the strong values of FreeBSD is its stability. For fun I
recently booted a 4BSD-something on a VAX emulator and immediately felt at
ease, because of this stability. I perceive rust, despite some of its
technical merits, as unable to provide that kind of stability. This language
is a fast and (still) unstable moving target, so fast that once integrated it
will immediately be obsolete on release. The integrated version would probably
only be usable to compile base, countless other packaged versions would be
required to compile ports---I'm also thinking about llvm here. That is bound
to be a maintenance nightmare, for the FreeBSD teams and for the users alike.

	After reading the pros and cons posted on the mailing list, merging
them with my own experience, I think rust should be avoided at all costs from
being integrated into base, no part of base should ever be written in rust.
However, if rust needs something for a proper usage from ports such as kernel
interfaces, linking facilities, etc., we should provide it from base.

-- 
%!PS -- Bertrand Petit
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