Given that `StableVec` behaves similarly to a map, it may make sense to implement Entry API for it like [`HashMap`'s](https://doc.rust-lang.org/stable/std/collections/hash_map/struct.HashMap.html#entry-api) and [`BTreeMap`'s](https://doc.rust-lang.org/std/collections/struct.BTreeMap.html#entry-api). `StableVec` can be used to insert keys at an arbitrary index if you call `.reserve_for()` before `.insert()`.
Given that
StableVecbehaves similarly to a map, it may make sense to implement Entry API for it likeHashMap's andBTreeMap's.StableVeccan be used to insert keys at an arbitrary index if you call.reserve_for()before.insert().