> I do agree though that an ordered map would nicely solve the issue.
To be precise, Rust does provide an ordered map in the standard library, it's std::collections::BTreeMap. However, iteration order is key comparison order, not insertion order.
To be precise, Rust does provide an ordered map in the standard library, it's std::collections::BTreeMap. However, iteration order is key comparison order, not insertion order.
Java's had that forever, but it's not really a common use case.
I wish they provided a sort method to re-sort and re-index the vector to change the iteration order without the space overhead of creating a and sorting a separate vector/list of keys (or key-value pairs, depending on use case. You might want to change iteration order based on the currently held value).
Technically pypy and I believe php implemented this model first, though it's probably most well known from cpython (for which it had been proposed first, by raymond hettinger).