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carlos .
carlos .
9,703 Points

song lists not rendering to page: here's all the formatted files.

snapshot: https://w.trhou.se/igo4fbnfcn


Uncaught ReferenceError: song is not defined
    at Playlist.add (playlist.js:7)
    at app.js:6


var playlist = new Playlist();

var hereComesTheSun = new Song("Here Comes The Sun", "The Beatles", "2:54");
var walkingOnSunshine = new Song("Walking on Sunshine", "Katrina and the Waves", "3:43");


var playlistElement = document.getElementById("playlist");
playlist.renderInElement = function(list){
list.innerHTML = "";
  for(var i = 0; i < this.songs.length; i++) {
    list.innerHTML += this.songs[i].toHTML(); 


function Playlist() {
this.songs= [];
this.nowPlayingIndex = 0;

Playlist.prototype.add = function() {

Playlist.prototype.play = function() {
var currentSong = this.songs[this.nowPlayingIndex]; 

Playlist.prototype.stop = function(){
var currentSong = this.songs[this.nowPlayingIndex];

Playlist.prototype.next = function() {
this.nowPlayingIndex ++;
if(this.nowPlayingIndex === this.songs.length){
  this.nowPlayingIndex = 0;

// this.play(); 

Playlist.prototype.renderInElement = function() {



function Song(title, artist, duration) {
this.title = title;
this.artist = artist;
this.duration = duration; 
this.isPlaying = false; 

Song.prototype.play = function() {
this.isPlaying = true; 

Song.prototype.stop = function() {
this.isPlaying = false; 

Song.prototype.toHTML = function() {
 var htmlString =  '<li';
      htmlString += ' class="current"';
htmlString += '>';
htmlString += this.title;
htmlString += '  -  ';
htmlString += this.artist; 
htmlString +- '<span class="duration">';
htmlString += this.duration;
htmlString += '</span></li>';
  return htmlString; 


<!DOCTYPE html>
    <link rel="stylesheet" href="style.css"/>



        <ol id="playlist">
        <button id="play">Play</button>
        <button id="next">Next</button>
        <button id="stop">Stop</button>


    <script src="playlist.js"></script>
    <script src="song.js"></script>
    <script src="app.js"></script>




@import url(http://fonts.googleapis.com/css?family=Varela+Round);
@import url(http://necolas.github.io/normalize.css/3.0.2/normalize.css);

body {
    background: #ECEEEF;
    text-align: center;
    margin: 100px auto;
    width: 80%;
    padding: 0 40px;
    font: 14px normal 'Varela Round', Helvetica, serif;

h1 {
    font-size: 20px;

div {
    background: #c25975;
    border-radius: 4px;
    border: 1px solid #D5DDE4;
    margin: -40px 0 0;

ol {
    list-style-type: none;
    padding: 0;
    margin: 0 0;
    width: 100%;
    display: inline-block;


li {
    color: #2C3238;
    width: 96%;
    padding: 15px 2%;
    margin: 0;
    text-align: left;
    border-top: 1px solid #D5DDE4;

li span {
    float: right;
    color: #777B7E;

li.current {
    background: #ffd7d8;

button {
    padding:10px 35px;
    border: none;
    border-radius: 5px;
    background: white;


4 Answers

Just taking a glance, your function definition doesn't take any parameters, it should read Playlist.prototype.add = function(song), whereas at the moment it's empty. The error is telling you that in this function scope, 'song' isn't recognized.

carlos .
carlos .
9,703 Points

Yeah I tried that before. When I pass in song an error is no longer generated. But still don't get rendered html. So there still must be something else missing.

Playlist.prototype.add = function(song) {

playlist.renderInElement() doesn't get called anywhere that I can tell. If I'm reading this correctly, it looks like what you'd need to do would be to call playlist.renderInElement(playlistElement) at the end of app.js?

carlos .
carlos .
9,703 Points

hmmm. I do have that on line 10 of app.js

Dom Farnham
Dom Farnham
19,421 Points

Try adding song as a parameter when defining your Playlist.add method.

Playlist.prototype.add = function (song) {

Oh, it's not there in the app.js snippet that you have up, it sounds like you may be running a different version of app.js locally than what is posted at this point.