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JavaScript

Posted by Deidre Fuelling
Deidre Fuelling
5,647 Points

playList shows as undefined. What did I do wrong?

See below & advise. Please!

var playList = [
  'I Did It My Way',
  'Respect',
  'Imagine',
  'Born to Run',
  'Louie Louie',
  'Maybellene'
];

function print(message) {
  document.write(message);
}

function printList(list) {
  var listHTML = '<ol>';
  for ( var i = 0; i < list.length; i += 1); {
    listHTML += '<li>' + list[i] + '</li>';
  }
  listHTML += '</ol>';
  print(listHTML);
}
printList(playList);
Chyno Deluxe
Chyno Deluxe
16,936 Points

//Fixed Code Preview

3 Answers

Karolin Rafalski
Karolin Rafalski
11,368 Points
Karolin Rafalski
Karolin Rafalski
11,368 Points

Remove the semi-colon after the )

Change this:

for ( var i = 0; i < list.length; i += 1); { listHTML

To this:

for ( var i = 0; i < list.length; i += 1) { listHTML
Deidre Fuelling
Deidre Fuelling
5,647 Points
Deidre Fuelling
Deidre Fuelling
5,647 Points

That worked. Thank you!

Seth Kroger
Seth Kroger
56,416 Points
Seth Kroger
Seth Kroger
56,416 Points

A for statement shouldn't have a semi-colon after the parentheses, it should go straight to the curly brace. Otherwise you end up with an empty for loop. The syntax is technically allowed, so it doesn't cause an syntax or parse error, but is almost always not what you want.

  for ( var i = 0; i < list.length; i += 1); { // wrong... 
  }
  for ( var i = 0; i < list.length; i += 1) { // right... 
  }