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                <div id="myLibrary"></div>

var instance = new myLib({
	selectorID: '#myLibrary',
	text: 'Hello Earth!',
	color: 'red'





	// Merge options and initialize library
	const myLib = function(opts) {

		// Merge default options with user options
		this.options = Object.assign(myLib.defaults, opts);
		// Merge support for IE11
		/*function merge_options(defaults,user_options) {
			let new_options = {};
			let attrname;
			for (attrname in defaults) {
				new_options[attrname] = defaults[attrname];
			for (attrname in user_options) {
				new_options[attrname] = user_options[attrname];
			return new_options;
		this.options = merge_options(myLib.defaults,opts);*/

		// Define merged options
		this.selector = document.querySelector(this.options.selector);
		this.text = this.options.text;
		this.color = this.options.color;

		// initialize library

	// library logic
	myLib.prototype.init = function() { = this.color;
		this.selector.innerHTML = this.text;

	// Define default options
	myLib.defaults = {
		selector: '',
		text: 'Hello World!',
		color: 'black'

	// Make accessible globally
	window.myLib = myLib;

// THis normally goes in the HTML after including the library script. This is only here for demo porpuses
var instance = new myLib({
	selector: '#myLibrary',
	text: 'Hello Earth!',
	color: 'red'