How to unpack a `set`?

[stolyaroleh]

I am using Starlark (and starlark-rust) as a configuration language, and would love to be able to use sets.
Unfortunately, I cannot extract any values from them - SetData is pub (crate).

Is there any harm in exposing it? Would you accept a PR?

[stepancheg]

Is there any harm in exposing it?

That would make harder to change implementation (for example, implement it similarly to list, on the heap).

(Also SetData cannot be simply made public, because this is not actual representation of set type in starlark).

Instead, utilities similar to dict can be implemented/exposed like

https://docs.rs/starlark/latest/starlark/values/dict/struct.UnpackDictEntries.html
https://docs.rs/starlark/latest/starlark/values/dict/struct.DictRef.html

Disclaimer: I no longer work on starlark-rust, so this is just my opinion.