Underscore.js

Underscore is a free JavaScript library with functions for everyday JavaScript tasks. It was created as a tool collection for container operations on arrays and objects as well as JavaScript functions 2009 by Jeremy Ashkenas ( Backbone.js, CoffeeScript ). The library name derives from the reserved for them global object _ (Underscore is English for the character underscore) analogous to the object $ in jQuery ago.

Underscore follows the paradigm of functional programming and builds complex operations by composition of simple functions. There dispense with the otherwise often used in JavaScript extension of object prototypes in favor of a continuous auxiliary classes semantics.

Browser Compatibility

To test the browser compatibility is a separate test suite available which gave a compatibility with Internet Explorer version 6.0 and Chrome 28, Opera 12 and Firefox 22 (all tested with version 1.5.1 on Windows 7 64 bit, respectively, with IETester ).

To ensure the best possible performance current language elements are used underscore internally, if they are available on each platform. For example, delegated the function _.each ( ) to the native implementation of Array.prototype.forEach (), if it exists, otherwise provides Underscore provides its own implementation.

Trivia

The documentation describes Underscore as:

" Underscore is a utility -belt library ... the tie to go along with jQuery 's tux, and Backbone.js ' s suspenders. "

" Underscore is a tool belt library for jQuery ... the tuxedo matching tie ( tie ) and liner ( braces ) for Backbone.js. "