Phelype Oleinik

> We cannot do that because the package does not need to be loaded. Could > we test if the base form is indexed somewhere? Hmm, yes, you are right...

> From a naming perspective it wouldn't be wrong to make sure that the base forms do exist e.g. have \use:N that would allow to use \use:N \foo_bar without braces...

> Actually, maybe a solution is to try and keep all this variant info in > the index, indexing uses of each variant separately. So the index would > contain...

Hmm... Indeed, it looks pretty, but form a practical point of view it does take too much space... > secondly, if you start doing this then you probably would need...

> No idea on the letter. `f` might be misleading as it is an expansion type in `expl3` but I can't think of something more reasonable. Well, `o` is also...

> IIRC many verbatim packages read lines one by one and typeset them directly without waiting for the end of the environment. Should we provide something like that? If I...

Hm, yes, I forgot about `\~`... Well, with the current mechanism there's really no way to fit both `~` and `\~`, because `\DeclareRobustCommand` will define `\~␣` for both since it...

> * the uses in `texmf` directory is not controlled by latex2e hence should be intact Yes > * `\@expl@cs@argument@spec@@N` need to be renamed to `\@expl@cs@parameter@spec@@N`. > Will this change...

@josephwright Yeah, in most cases it won't be noticeable, except when a not-too-old (i.e. `\@expl@cs@argument@spec@@N` already exists) kernel trying to roll forward... But I believe I can count the number...

I can take a look, to see what's needed to fully support roll forward for this case. If the main target is to support what version of LaTeX Overleaf has,...