stable-block-arena

Block-allocated arena with stable handles that survive compaction

Features

• Stable handles: Removing elements doesn't invalidate handles to other elements
• Block-based storage: Memory is allocated/deallocated in fixed-size blocks instead of per-element
• Compaction: Reclaim memory from removed elements
• Zero-cost abstractions: Handles are just u32 wrappers

Use Cases

• Entity-component systems
• Graph data structures
• Resource managers
• Virtual machine object pools
• Any scenario requiring stable references with dynamic allocation

Example

use stable_block_arena::Arena;

let mut arena = Arena::new();

let hello = arena.insert("hello");
let world = arena.insert("world");

arena.remove(hello);

// Handle is still valid! 
assert_eq!(arena.get(world), Some(&"world"));

// Reclaim memory blocks from removed elements
arena.compact(|_| true);

// Handle is still valid after compaction!
assert_eq!(arena.get(world), Some(&"world"));

// Remove 'world' during compaction
arena.compact(|handle| handle != world);

// World has been removed during compaction
assert_eq!(arena.get(world), None);

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.