tables containing `Set` values are serializable but corresponding deserialized `Arrow.Table`s are inaccessible about arrow-julia

[quinnj]

Yes, as you've discovered, the Arrow.jl implementation isn't currently very useful for "serialization" of generic objects, but focused on the limited set of types it was originally designed for. I've looked into this and the DataType cases and they're non-trivial with how the code is currently structured, but it should be much nicer if people want to "hook in" to using Arrow.jl for generic serialization. The biggest thing is making the ArrowTypes module much cleaner in terms of the contracts for the various types: what's required and then making sure hte implementation only relies on those contracts. Then people can overload the necessary methods and everything will just work, similar to the StructTypes.jl system. let me look at the NamedTuple issue and see if it's lower hanging fruit

[jrevels]

Ha, yeah - I was actually surprised that Sets were serializable in the first place 😁 Thanks for checking it out.

I'd consider it a win if the error could be moved to serialization time (and try to prevent non-deserializable content from being serialized in the first place as a general rule)

[quinnj]

I'm going to add support for this in #156