Struct ChoiceIndexer 

pub struct ChoiceIndexer { /* private fields */ }

Assigns sequential indices to concurrent streams in first-come-first-served order.

When multiple concurrent streams need unique indices, this struct ensures each stream gets the next available index. The first stream to request an index for a given native key gets index 0 (or initial), the next gets 1, etc.

Thread-safe: uses atomic operations and concurrent hash map.

Implementations

impl ChoiceIndexer

pub fn new(initial: u64) -> Self

Creates a new choice indexer starting from the given initial value.

pub fn get(&self, native_index: usize) -> u64

Gets the index for a native key, assigning the next available index if new.

First-come-first-served: the first caller for a given native key gets the current counter value, then the counter increments for the next caller.