TheBox193

/**
 * Removes all falsy and undefined values from an object
 * @param  {object} o Object to be compacted
 * @return {object}   Compact Object
 * @link http://stackoverflow.com/a/14058408/417822
 */
_.mixin({'compactObject': function(o) {
	var clone = _.clone(o);

	_.each(clone, function(v, k) {

TheBox193

Collection1 = Backbone.Collection.extend({
	initialize: function(models, options){
		// bad, causes things to crash if options.that doesn’t get passed.
		this.doSomethingWithThat(options.that);
	}
});

// Crashes since 'that' is not set
collection1 = new Collection1();