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 * Create a new object composed of properties that meet specific criteria
 * (c) 2021 Chris Ferdinandi, MIT License,
 * @param  {Object}   obj      The original object
 * @param  {Function} callback The callback test to run
 * @return {Object}            The new, filtered object
function objectFilter (obj, callback) {

	// Setup a new object
	let filtered = {};

	// Loop through each item in the object and test it
	for (let key in obj) {
		if (, key)) {

			// If the callback validates true, push item to the new object
			if (callback(obj[key], key, obj)) {
				filtered[key] = obj[key];


	// Return the new object
	return filtered;


let lunch = {
	sandwich: 'turkey',
	drink: 'soda',
	desert: true,
	chips: 'Cape Cod'

let filtered = objectFilter(lunch, function (val) {
	return val.length > 5;