lodash.flow

What is lodash.flow?

The lodash.flow package is a utility library that allows you to create a function pipeline by composing multiple functions. It is part of the Lodash library, which is a popular utility library for JavaScript. The flow function takes multiple functions as arguments and returns a new function that, when invoked, passes its arguments through each of the original functions from left to right.

What are lodash.flow's main functionalities?

Function Composition

This feature allows you to compose multiple functions into a single function. In the example, the composedFunction applies the add, multiply, and subtract functions in sequence to the input value.

const _ = require('lodash.flow');

const add = (x) => x + 1;
const multiply = (x) => x * 2;
const subtract = (x) => x - 3;

const composedFunction = _.flow([add, multiply, subtract]);

console.log(composedFunction(5)); // Output: 9

Data Transformation

This feature is useful for transforming data through a series of functions. In the example, the transform function converts a string to uppercase, appends an exclamation mark, and then splits it into an array of words.

const _ = require('lodash.flow');

const toUpperCase = (str) => str.toUpperCase();
const appendExclamation = (str) => str + '!';
const splitWords = (str) => str.split(' ');

const transform = _.flow([toUpperCase, appendExclamation, splitWords]);

console.log(transform('hello world')); // Output: [ 'HELLO', 'WORLD!' ]

Other packages similar to lodash.flow

ramda

Ramda is a functional programming library for JavaScript that provides a wide range of utility functions, including function composition. It is similar to lodash.flow but offers a more comprehensive set of functional programming tools.

compose-function

compose-function is a small utility library that provides a simple way to compose functions. It is similar to lodash.flow but is more lightweight and focused solely on function composition.

redux

Redux is a state management library for JavaScript applications. While its primary purpose is not function composition, it provides a compose function that can be used to achieve similar functionality to lodash.flow.

README

lodash.flow v3.5.0

The lodash method _.flow exported as a Node.js module.

Installation

Using npm:

$ {sudo -H} npm i -g npm
$ npm i --save lodash.flow

In Node.js:

var flow = require('lodash.flow');

See the documentation or package source for more details.