An all-you-can-eat buffet of high-performance, persistent, immutable, functional data structures. Collect them all!

Note: This library is an ongoing work in progress. The data structures mentioned below are all working nicely, but will probably have additional methods introduced as time goes on, and there may be some breaking changes in future versions when work commences to iron out API inconsistencies between data structures. Documentation is also somewhat lacking and out of date, but take a look at the functions folder for each data structure package, which is almost as good as actual documentation, due to the one-operation-per-file policy, and the comprehensive TypeScript annotations.

• A robust suite of high-performance data structures for most use cases
• Full ES2015 module support so that your application bundle only need grow in size according to what you actually use
• Functional API, prioritising an order of parameters best suited for currying and composition
• 🚧 API for deep operations on nested structures
• Deep and shallow conversion to and from native types, including arrays, objects, iterables, Maps and Sets
• Complete set of TypeScript definitions
• Extensive documentation and examples
• One package import to access everything, or isolated npm packages for each individual data structure
• Comprehensive unit test suite, consisting of hundreds of tests for every data structure
• Strong focus on a code style that emphasises high performance internally

• [ List ] A persistent list/vector structure based on a modified RRB Tree implementation.
• [ Map ] A persistent hash map, mapping keys to values. Implemented as a Clojure-style hash array mapped trie.
• [ Sorted Map ] A persistent sorted map backed by a red-black tree and a hash map with user-definable sort order.
• [ Set ] A persistent set, backed by a hash map.
• [ Sorted Set ] A persistent sorted set backed by a red-black tree and a hash map, with user-definable sort order.
• [ Red Black Tree ] A persistent red-black tree, providing a balanced binary search tree which maps keys to values.

See the road map for information on further development and plans for additional features and data structures.

# via NPM
npm install collectable

# or Yarn
yarn add collectable

TypeScript type definitions are built in.

API Reference: [ General | List | Map | Sorted Map | Set | Sorted Set | Red Black Tree | Others... ]

• Map implementation adapted from Tylor Steinberger's TypeScript conversion of Matt Bierner's HAMT implementation.

Want to help out? See the guide for contributors.