greek babel broken on texlive 2023

[dginev]

Using the greek package option of babel now produces a Fatal error in texlive 2023 on my device. Minimal example:

\documentclass{article}
\usepackage[greek,english]{babel}

\begin{document}
\textgreek{dry run}
\end{document}

latexml log:

latexmlc (LaTeXML version 0.8.8; revision 2233d877)
processing started Mon Oct 14 17:38:09 2024
Error:undefined:\IfFormatAtLeastTF The token T_CS[\IfFormatAtLeastTF] is not defined. at greek.ldf; line 601 col 20
Info:latex:(babel)  Package babel Info: Importing at babel-english.tex; line 11 col 0
Info:latex:(babel)  Package babel Info: Importing at babel-greek.tex; line 11 col 0
Fatal:misdefined:\bbl@line Expansion of '\bbl@line' has unbalanced {}
	at babel-greek.tex; line 11 col 0 - line 11 col 1
	Expansion is sigma.final.3.0 = { ()"()[σΣ] } }sigma.final.3.1 = { remove }[transforms.posthyphenation]diaeresis.hyphen.1.0 = { |([ϊΐϋΰ]) }diaeresis.hyphen.1.1 = { remove }diaeresis.hyphen.1.2 = { no = {1}, pre = -, post = {1|ϊΐϋΰ|ιίυύ} }
	In Core::Definition::Primitive[\read Num... /home/deyan/perl5/lib/perl5/LaTeXML/Engine/TeX_FileIO.pool.ltxml; line 76
	 <= Core::Stomach[@0x644d3b9e7748] <= Core::Definition::Primitive[Begin] <= Core::Stomach[@0x644d3b9e7748] <= Core::Definition::Primitive[Begin] <= Core::Stomach[@0x644d3b9e7748] <= Core::Gullet[@0x644d3b9e0138] <= Core::Stomach[@0x644d3b9e7748] <= Core::Definition::Constructor[\usepac... <= Core::Stomach[@0x644d3b9e7748]
Conversion complete: 1 error; 1 fatal error; 1 undefined macro[\IfFormatAtLeastTF] (See /home/deyan/git/my-LaTeXML/test.latexml.log)

$ tex --version
TeX 3.141592653 (TeX Live 2023/Debian)
kpathsea version 6.3.5

CC @brucemiller some fresh food for thought for our recent conversation touching on texlive regressions. I expect a latex profile including expl3 will fix this by default, but the way I encountered it was quite unfortunate (no HTML was generated at all).

[teepeemm]

Speaking of expl3, where are we on that? Do you (plural) think you'll have something in the next few weeks, or is a year timeline more likely? Is there a way anyone else can help out? Should others try to roll up their sleeves and consider wading into that?
I guess the same could be asked about performance in general and the rumored Rust rewrite.

[dginev]

@teepeemm I think the expl3 regression (and v0.8.9) is somewhere in the "months" timescale from end of Nov 2024.

The Rust rewrite may go public in the next couple of months, in a pre-alpha state, as we may add a contributor or two from Cornell Uni.

I think it is much easier to help me (as in, the Rust work) than to help Bruce, since he is doing a very large reorganization of the LaTeXML kernel/engine, which requires a lot of decisions on interfaces, organization, stage separation...

There is a non-zero chance a fix may exist by end of 2024, and hopefully a high chance it exists in early to mid-2025.

[dginev]

@teepeemm I should also mention 2024 has been a somewhat unkind year to LaTeXML development speeds, as there were high levels of funding and team turbulence. As one example, I now work for arXiv, and my main work is only partially related to LaTeXML development. Which could change when winds improve direction...