Alternatives to underscore.js
I know this is old but did you look at lodash? From the site:
A drop-in replacement* for Underscore.js.[...]
Custom builds make it easy to create lightweight versions of Lo-Dash containing only the methods you need. To top it off, we handle all method dependency and alias mapping for you.
Take a look at lazy.js (http://dtao.github.io/lazy.js/) similar to underscore.js but with significant performance improvment due to lazy evaluation
It's called JavaScript arr.filter , arr.sort , arr.length.
You can apply any array method on an array, popular ones are filter, map and reduce, You can build more complex operations by combining those.
If you want to iterate over objects use
Object.keys(o).forEach(function (key) { var val = o[key]; ...});underscore is useful if you live in an ES3 world, but ES5 has everything you need, all underscore does is add bloat on top of it.