lodash v4.0.0
2015 was big year! Lodash became the most depended on npm package, passed 1 billion downloads, & its v3 release saw massive adoption!
The year was also one of collaboration, as discussions began on merging Lodash & Underscore. Much of Lodash v4 is proofing out the ideas from those discussions. Lodash v4 would not be possible without the collaboration & contributions of the Underscore core team. In the spirit of merging our teams have blended with several members contributing to both libraries.
For 2016 & lodash v4.0.0 we wanted to cut loose, push forward, & take things up a notch!
Modern only
With v4 we’re breaking free from old projects, old environments, & dropping old IE < 9 support!
4 kB Core
Lodash’s kitchen-sink size will continue to grow as new methods & functionality are added. However, we now offer a 4 kB (gzipped) core build that’s compatible with Backbone v1.2.4 for folks who want Lodash without lugging around the kitchen sink.
More ES6
We’ve continued to embrace ES6 with methods like _.isSymbol, added support for cloning & comparing array buffers, maps, sets, & symbols, converting iterators to arrays, & iterable _(…).
In addition, we’ve published an es-build & pulled babel-plugin-lodash into core to make tree-shaking a breeze.
More Modular
Pop quiz! 📣
What category path does the bindAll method belong to? Is it
A) require('lodash/function/bindAll')
B) require('lodash/utility/bindAll')
C) require('lodash/util/bindAll')
Don’t know? Well, with v4 it doesn’t matter because now module paths are as simple as
var bindAll = require('lodash/bindAll');We’ve also reduced module complexity making it easier to create smaller bundles. This has helped Lodash adoption with libraries like Async & Redux!
1st Class FP
With v3 we introduced lodash-fp. We learned a lot & with v4 we decided to pull it into core.
Now you can get immutable, auto-curried, iteratee-first, data-last methods as simply as
var _ = require('lodash/fp');
var object = { 'a': 1 };
var source = { 'b': 2 };
var newObject = _.assign(source)(object);
console.log(newObject);
// => { 'a': 1, 'b': 2 }
console.log(object);
// => { 'a': 1 }
var convert = require('lodash/fp/convert');
var assign = convert('assign', require('lodash.assign'));
// works too!Chakra Optimized
Well actually, while we’re excited about Chakra, Lodash is optimized for great performance across all engines. Unlike many libraries, we don’t favor a single engine so we can deliver solid performance & support regardless of engine.
With v4 we’ve continued our commitment to performance; expanding support for lazy evaluation & improving the performance of core functionality like circular reference detection.
Emojis
Taking things up a notch Lodash v4 has added support for emojis! Includes things like
astral symbols, unicode modifiers, variation selector characters, zero-width joiners, & regional indicator symbols.
Breaking changes
We’ve introduced more breaking changes in this release than any other so be sure to check out the changelog for a full rundown of changes & give lodash-migrate a spin to help migrate older Lodash code to the latest release.
If you dig Lodash don’t forget to star the repo or npm star lodash!