[][src]Crate thunderdome

GitHub CI Status thunderdome on crates.io thunderdome docs

Thunderdome is a ~gladitorial~ generational arena inspired by generational-arena, slotmap, and slab. It provides constant time insertion, lookup, and removal via small (8 byte) keys returned from Arena.

Thunderdome's key type, Index, is still 8 bytes when put inside of an Option<T> thanks to Rust's NonZero* types.

Basic Examples

let mut arena = Arena::new();

let foo = arena.insert("Foo");
let bar = arena.insert("Bar");

assert_eq!(arena[foo], "Foo");
assert_eq!(arena[bar], "Bar");

arena[bar] = "Replaced";
assert_eq!(arena[bar], "Replaced");

let foo_value = arena.remove(foo);
assert_eq!(foo_value, Some("Foo"));

// The slot previously used by foo will be reused for baz
let baz = arena.insert("Baz");
assert_eq!(arena[baz], "Baz");

// foo is no longer a valid key
assert_eq!(arena.get(foo), None);

Comparison With Similar Crates

Generational Indices¹YesYesYesNo
Max Elements2³²2⁶⁴2³²2⁶⁴
Non-Copy ValuesYesYesSorta²Yes
no_std SupportNoYesNoNo
Serde SupportNoYesYesNo
  1. Generational indices help solve the ABA Problem, which can cause dangling keys to mistakenly access newly-inserted data.
  2. slotmap's SlotMap and HopSlotMap require values to be Copy on stable Rust versions. slotmap's DenseSlotMap type supports non-Copy types on stable, but has different performance trade-offs.

Minimum Supported Rust Version (MSRV)

Thunderdome supports Rust 1.34.1 and newer. Until Thunderdome reaches 1.0, changes to the MSRV will require major version bumps. After 1.0, MSRV changes will only require minor version bumps, but will need significant justification.



Container that can have elements inserted into it and removed from it.


See Arena::drain.


Index type for Arena that has a generation attached to it.


Iterator typed used when an Arena is turned IntoIterator.


See [Arena::iter][Arena::iter].


See [Arena::iter_mut][Arena::iter_mut].