raviqqe / hamt

Immutable and Memory-Efficient Maps and Sets in Go

hamt

For the old any-based API, refer to the main branch.

Immutable and Memory Efficient Maps and Sets in Go.

This package hamt provides immutable collection types of maps (associative arrays) and sets implemented as Hash-Array Mapped Tries (HAMTs). All operations of the collections, such as insert and delete, are immutable and create new ones keeping original ones unmodified.

Hash-Array Mapped Trie (HAMT) is a data structure popular as a map (a.k.a. associative array or dictionary) or set. Its immutable variant is adopted widely by functional programming languages like Scala and Clojure to implement immutable and memory-efficient associative arrays and sets.

Installation

go get github.com/raviqqe/hamt/v2

Documentation

GoDoc

Technical notes

The implementation canonicalizes tree structures of HAMTs by eliminating intermediate nodes during delete operations as described in the CHAMP paper.

References

• Ideal Hash Trees
• Optimizing Hash-Array Mapped Tries for Fast and Lean Immutable JVM Collections

License

The Unlicense