Brian Chen

I believe the view-taking behaviour of `splitobs` predates MLUtils itself? Might be worth having a discussion about its semantics there.

Also no strong feelings either way, but we if we don't want to support we should add the functionality as deprecated so that it's not a breaking change on the...

For the interested, here's how Optimisers.jl handles reverse mode friendly (un)flattening: https://github.com/FluxML/Optimisers.jl/blob/master/src/destructure.jl. We opted for the conservative approach and only consider non-integer numeric arrays (due in part to Flux's design...

Yes, Functors.jl is an integral part of it but there's no reason a similar set of functionality couldn't be developed for another parameter handling library :)

> An approach like `x_flat, reconstruct_function = flatten(x)` didn't work out performance/type-stability wise, there was trouble when things were nested more deeply (though maybe I did it wrong, I also...

AFAIK something like https://github.com/rafaqz/FieldMetadata.jl could be that standard, but the note at the top of the README seems to suggest differently :/

Looks like this was caused by a change on the SciML side: https://github.com/SciML/SciMLBase.jl/commit/62494689ad8f198fb75b7170aeb56f837b4590e3. You could ask them to implement the suggestion in https://github.com/FluxML/Zygote.jl/issues/1293#issuecomment-1243051361 and see if that works.