cargo crates.io codecov Hits-of-Code Lines of code License docs.rs

At least 5x faster alternative of HashMap, for very small maps. It is also faster than FxHashMap, ArrayMap. The smaller the map, the higher the performance. When the map is larger than 50, it is better to use standard HashMap, since the performance of micromap::Map may start to degrade.

The only important restriction is that both key and value must implement the Copy trait.

WELCOME: Not all functions that a user expects to have in a map are implemented. I will appreciate if you contribute by implementing these missing functions.

Here is how you use it:

rust use micromap::Map; let mut m : Map<u64, &str, 10> = Map::new(); m.insert(1, "foo"); m.insert(2, "bar"); assert_eq!(2, m.len());

Pay attention, here the map is created with an extra generic argument 10. This is the total size of the map, which is allocated on stack when ::new() is called. Unlike HashMap, the Map doesn't use heap at all.

Read the API documentation. The struct micromap::Map is designed as closely similar to std::collections::HashMap as possible.

How to Contribute

First, install Rust and then:

bash $ cargo test -vv

If everything goes well, fork repository, make changes, send us a pull request. We will review your changes and apply them to the master branch shortly, provided they don't violate our quality standards. To avoid frustration, before sending us your pull request please run cargo test again. Also, run cargo fmt and cargo clippy.