Fast, modern, and practical utility library for FP in TypeScript.

Documentation

Full documentation can be found here.

Features

• 🚀 built with ReScript, which generates highly performant JavaScript code (see the benchmark results here)
• 👀 provides more readable code, due to the data-first approach
• ✨ supports TypeScript and Flow
• 🛡 helps you write safer code with Option and Result types
• 🎯 all functions return immutable data (no side-effects)
• 🌲 tree-shakeable
• 📝 fully documented

Getting started

Installation

yarn add @mobily/ts-belt

or with npm

npm install @mobily/ts-belt --save

Usage

Module	Namespace	Description
Array	A	Utility functions for Array.
Boolean	B	Utility functions for Boolean.
Number	N	Utility functions for Number.
Object (Dict)	D	Utility functions for Object.
String	S	Utility functions for String.
Guards	G	Various TypeScript guards.
Option	O	Functions for handling the Option data type that represents the existence and nonexistence of a value.
Result	R	Functions for describing the result of a certain operation without relying on exceptions.
Function	F	Other useful functions.

import { A, O, N, pipe } from '@mobily/ts-belt'

pipe(
  [1, 2, 3, 4, 5], // → [1, 2, 3, 4, 5]
  A.dropExactly(2), // → Some([3, 4, 5])
  O.flatMap(A.head), // → Some(3)
  O.map(N.multiply(10)), // → Some(30)
  O.getWithDefault(0), // → 30
) // → 30

Contributors

Marcin Dziewulski 💻 📖 ⚠️ 🎨 🚧	Krzysztof Lenda 📖	Radek Kozieł 📖	Artur 📖	Dominik Łopaciński 💻 📖 ⚠️	Jakub Wąsik 📖	Krystian Mateusiak 💻 📖 ⚠️
Michał Miszczyszyn 🤔	Kevin 📖	Anthony Khong 💻 📖 ⚠️	Pyrolistical 📖 🚧 🤔	Mathieu Acthernoene 🤔

License

The MIT License.

See LICENSE