Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript

Posted by Anna Litynska
Anna Litynska
2,346 Points

Why do we have to give the 'list' value to the function?

Why do we have to give the 'list' value to the function 'printList' if the 'list' is not defined anywhere?

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);

1 Answer

simhub
simhub
26,544 Points

Hi Anna, 'list ' is a Parmater(or placeholder) It exists only inside the function scope ( in this case, between the two curlybraces {} )

After invoking this Funktion you assign what ever value you like to it Parameter (in other words/ fill the placeholder 'list' with the value of 'playList' )

Anna Litynska
Anna Litynska
2,346 Points

Thanks!