lodash v3.0.0

The modern build of lodash exported as Node.js/io.js modules.

Generated using lodash-cli:

$ lodash modularize modern exports=node -o ./
$ lodash modern -d -o ./index.js

Installation

Using npm:

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

In Node.js/io.js:

// load the modern build
var _ = require('lodash');
// or a method category
var array = require('lodash/array');
// or a method
var chunk = require('lodash/array/chunk');

See the package source for more details.

Note:
Don’t assign values to the special variable _ when in the REPL.
Install n_ for a REPL that includes lodash by default.

Module formats

lodash is also available in a variety of other builds & module formats.

• npm packages for modern, compatibility, & per method builds
• AMD modules for modern & compatibility builds
• ES modules for the modern build

Further Reading

• API Documentation
• Build Differences
• Changelog
• Release Notes
• Roadmap
• More Resources

Features not in Underscore

• ~100% code coverage
• Follows semantic versioning for releases
• Lazily evaluated chaining
• _(…) supports intuitive chaining
• _.ary & _.rearg to change function argument limits & order
• _.at for cherry-picking collection values
• _.attempt to execute functions which may error without a try-catch
• _.before to complement _.after
• _.bindKey for binding “lazy” defined methods
• _.chunk for splitting an array into chunks of a given size
• _.clone supports shallow cloning of Date & RegExp objects
• _.cloneDeep for deep cloning arrays & objects
• _.create for easier object inheritance
• _.curry & _.curryRight for creating curried functions
• _.debounce & _.throttle are cancelable & accept options for more control
• _.findIndex & _.findKey for finding indexes & keys
• _.flow to complement _.flowRight (a.k.a _.backflow & _.compose)
• _.forEach supports exiting early
• _.forIn for iterating all enumerable properties
• _.forOwn for iterating own properties
• _.includes accepts a fromIndex
• _.isError to check for error objects
• _.isNative to check for native functions
• _.isPlainObject & _.toPlainObject to check for & convert to Object objects
• _.isTypedArray to check for typed arrays
• _.keysIn & _.valuesIn for getting keys & values of all enumerable properties
• _.mapValues for mapping values to an object
• _.matches supports deep object comparisons
• _.merge for a deep _.extend
• _.parseInt for consistent cross-environment behavior
• _.propertyOf to complement _.property
• _.pull, _.pullAt, & _.remove for mutating arrays
• _.random supports returning floating-point numbers
• _.runInContext for collisionless mixins & easier mocking
• _.slice for creating subsets of array-like values
• _.sortByAll for sorting by multiple properties
• _.support for flagging environment features
• _.template supports “imports” options & ES template delimiters
• _.transform as a powerful alternative to _.reduce for transforming objects
• _.thru to pass values thru method chains
• _.xor to complement _.difference, _.intersection, & _.union
• _.bind, _.curry, _.partial, & more support customizable argument placeholders
• _.capitalize, _.trim, & more string methods
• _.clone, _.isEqual, & more accept callbacks
• _.dropWhile, _.takeWhile, & more to complement _.first, _.initial, _.last, & _.rest
• _.findLast, _.findLastIndex, & more right-associative methods
• _.includes, _.toArray, & more accept strings

Support

Tested in Chrome 39-40, Firefox 34-35, IE 6-11, Opera 25-26, Safari 5-8, io.js 1.0.4, Node.js 0.8.28 & 0.10.35, PhantomJS 1.9.8, RingoJS 0.11, & Rhino 1.7RC5.

Automated browser & CI test runs are available. Special thanks to Sauce Labs for providing automated browser testing.