Tiny functional programming suite for JavaScript.

pushedAt 3 years ago



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Check out the API docs!

The missing standard library for JavaScript. This lightweight library is meant to fill the gap between Ramda (functional) and Lodash (performance) while providing you with the tools you need to write sane JavaScript. This means that all functions treat data as immutable structures, compare objects by value instead of by reference, and offer the right mix of flexibility and composability.

  1. Why
  2. Usage
  3. Comparisons


First Class Functional Programming

Redash is designed to encourage functional programming styles without sacrificing the utility you're used to. What sets it apart is that, unlike some other libraries that simply offer FP-ish wrappers, functional programming is a first class citizen in Redash. Here's what that means for you:

  • Immutability — Redash will never mutate your data; objects are always shallowly copied.
  • Equality — Objects are compared by value, not reference. Work with data in a meaningful way without concerning yourself with how it's stored in memory.
  • Flexibility — Functional programming patterns don't always translate well to idiomatic JavaScript, so Redash takes the approach of pursuing functional programming patterns insofar as it produces understandable and idiomatic JavaScript. This means Redash sacrifices auto-curry and non-variadic functions for larger benefits such as performance, ES2015+ interop, and general utility.
  • Size — Redash comes in at just 12.6kb before gzip. Combine this with its use ES2015 modules and Rollup for module flattening, and you can rest easy when adding it to your project.
  • Simplicity — Redash strives to be as simple as possible despite its flexible API; it trades magic for explicitness, even at the cost of a few characters. For example, Lodash's get('foo.bar.baz') becomes getIn(['foo', 'bar', 'baz']), which is closer to Ramda's path(['foo', 'bar', 'baz']). This helps to eliminate confusion for less common cases that are nevertheless valid.

Built for the Next Generation of JavaScript

The Redash codebase is written with ES2015 modules and packaged with rollup so you to take advantage of tree shaking without the need for extra tooling. Redash also offers complete typings for TypeScript users so that you can work with its API with complete confidence.


# Yarn (Recommended)
yarn add redash

# NPM (Alternative)
npm install --save redash

After that's done, just import it in your code and get on to building awesome stuff. If you haven't already done so, you should check out the API documentation to see what functions are available and learn how to use them. Here are a few of the most common ways to use Redash:

ES2015 Module

import * as _ from 'redash'       // import everything
import { map, get } from 'redash' // or just what you need


const _ = require('redash')            // import everything
const { map, get } = require('redash') // or just what you need


If you have full control over your codebase and don't want to continually import/prefix all of the functions, you can install the library to a context.

import install from 'redash/installer'


// Now all of the functions are available on the scope you installed it to:
get('name', { name: 'Michael' }) // => 'Michael'


Category Redash Ramda Lodash Lodash/FP
Minified (kb) 12.6 44.7 71.4 71.4
100% Immutable Yes Yes No Yes
Auto-Curry No Yes No Yes
Object Equality Value Value Reference Reference
IE 9+ Yes Yes Yes Yes
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