"Unused global options" for class options

[Jellby]

It seems passing options to \documentclass triggers a "Unused global option(s)" warning, even if the options are obviously used:

\documentclass[journal=jctcce,manuscript=suppinfo]{achemso}
\title{Foo}
\begin{document}
Bar
\end{document}

LaTeX Warning: Unused global option(s):
    [journal=jctcce,manuscript=suppinfo].

[jfdoolster]

same thing here:

\documentclass[email=false]{achemso}
\title{foo}
\begin{document}
bar
\end{document}

Unused global option(s):
    [email=false].

[josephwright]

I'm wondering if I want to risk a fix here: would mean a change of option handler, and that's likely to cause wider issues

[jfdoolster]

I'm wondering if I want to risk a fix here: would mean a change of option handler, and that's likely to cause wider issues

not worth causing other issues, warning can be ignored similar to over/underfill

[fxcoudert]

I would argue this is actually a pain point: some TeX software knows that overfill/underfill are a different category and has options to silence them (or put them in a separate category). But class warnings are generally serious, and show up. This is the case in Overleaf for example, and having warnings that show up in all cases mean that users simply start ignoring all warnings, which is bad habit.

[josephwright]

I gave this a bit more thought. It's not actually an achemso issue per se as it's arisen due to changes in option handling more generally. Now, true, I could simply use a different option handling approach, but I will take a look at the underlying issue first.

[josephwright]

Right, we seem to have an idea where this comes from: definitely an xkeyval issue. I'm wondering about whether to move away to ltkeys, but that has some tricky aspects too.

[u-fischer]

It is imho a clear bug in the xkeyval package introduced in version 2.9 (2022/06/16). If I switch to an older xkeyval it works.

xkeyval tries to remove journal from the list journal=jctcce,manuscript=suppinfo, and that simply doesn't work with \@removeelement. It should either sanitize the list from journal=jctcce,manuscript=suppinfo to journal,manuscript, or change its method to remove an option.

[josephwright]

I've taken another look at a fix from the achemso end and it's simply too risky at the moment. We need the code to work with LaTeX from at least five if not 10 years ago, so any 'conditional' setup becomes horrible.

[josephwright]

Right, I decided that at this stage xkeyal can't be dropped, but I can force-suppress the warning, which I hope is acceptable.