I wanted to be able to use underscore in my controllers.

Make sure you include underscore.js on the page

First we will create a service or factory so we can inject it

var underscore = angular.module('underscore', []);
underscore.factory('_', ['$window', function() {
  return $window._;

Now we can use it like so:

// Declare it as a dependency of your module
var app = angular.module('app', ['underscore']);

// And then inject it on the controllers where you need it
app.controller('ListCtrl', function($scope, _) {
  // do stuff with underscore

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