Can we use babel/polyglossia hooks to avoid patching

[moewew]

See for example https://tex.stackexchange.com/q/529984/35864 (0691351) and Ulrike's comment https://tex.stackexchange.com/questions/529984/document-with-custom-bibliography-driver-compiling-with-babel-3-33-and-biblatex/529993?noredirect=1#comment1341156_529993.

It would be nice if we could avoid patching language selection macros. Maybe we can use existing hooks or ask for new hooks instead. Before I do that I need to understand exactly why we need to patch internal babel/polyglossia commands in the first place.

[jbezos]

It would be nice if we could avoid patching language selection macros.

Indeed. There are several hooks in babel. I'm not sure what you need, but if none of the existing hooks is useful for you, I'm willing to add a new one. Please, make a feature request. I'm working on a new version to be release in a few weeks, so I could add it.

[moewew]

I'm not sure what you need, but if none of the existing hooks is useful for you, I'm willing to add a new one. Please, make a feature request. I'm working on a new version to be release in a few weeks, so I could add it.

Great! As I wrote above I'll need some time to figure out what we actually need, but once I've done that I'll be sure to open a feature request.

[moewew]

I opened latex3/babel#55 with what I hope is an accurate description of what we need.

[moewew]

babel hooks were surprisingly easy: 02d5064. (Plus \AddtoBabelHook has been with us for so long that we can just remove the old code without backwards compatibility problems.)

Will have to wait and see if we can get rid of \pretocmd for polyglossia as well.

[plk]

@moewew - that's very good news - the patching was always a bit messy

[moewew]

There is a real (in the etoolbox sense) and documented hook in polyglossia now so we can avoid \pretocmd now and only need the much simpler \preto.

[moewew]

In db0b570 we switch from the beforeextras to the afterreset babel hook. Fingers crossed that everything still works.