Enum Collections for Rust

Enum Map is a special case of a Hash Map, with better computational complexity guarantees and overall performance.

Usage

EnumMap

Enum Map is a special case of a Hash Map, with better computational complexity guarantees and overall performance. Can differentiante between a missing (Option::None) and set (Option::Some) value.

```rust use enum_collections::{enummap, EnumMap, Enumerated};

[enum_collections]

enum Letter { A, B, }

let mut map: EnumMap = EnumMap::new(); map.insert(Letter::A, 42); assert_eq!(Some(&42u8), map.get(Letter::A)) ```

EnumTable

Enum Map is a special case of a Hash Map, with better computational complexity guarantees and overall performance. Initialized with default values, can NOT differentiate between missing values and values actually set.

```rust use enumcollections::{enumcollections, EnumTable, Enumerated}; #[enum_collections] enum Letter { A, B, }

let mut map: EnumTable = EnumTable::new(); map.insert(Letter::A, 42); asserteq!(&42u8, map.get(Letter::A)); asserteq!(&u8::default(), map.get(Letter::B)); ```

Benchmarks

There are single-threaded benchmarks for the get, insert and remove operations in enum-collections/benches. Invoke cargo bench to run them.

EnumMap

``` NAME lower bound | est | upper bound EnumMap get time: [635.02 ps 635.52 ps 636.06 ps] est ~22x faster std::collections::HashMap get time: [13.971 ns 13.986 ns 14.002 ns]

EnumMap insert time: [947.20 ps 947.83 ps 948.52 ps] est ~14,7x faster std::collections::HashMap insert time: [13.938 ns 13.964 ns 13.994 ns]

EnumMap remove time: [481.07 ps 481.79 ps 482.53 ps] est ~28,55x faster std::collections::HashMap remove time: [13.704 ns 13.737 ns 13.771 ns] ```

EnumTable

``` NAME lower bound | est | upper bound EnumTable get time: [485.65 ps 488.63 ps 491.59 ps] est ~0.95x faster Crate Enum-Map get time: [465.44 ps 465.93 ps 466.43 ps]

EnumTable insert time: [676.44 ps 677.17 ps 677.92 ps] est ~0.956x faster Crate Enum-Map insert time: [645.98 ps 647.60 ps 649.35 ps] ```