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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Using For Loops with Arrays

Stefan Cutajar
Stefan Cutajar
7,747 Points
Posted by Stefan Cutajar
Stefan Cutajar
7,747 Points

Why list is printing an extra blank line?

Hi, For some reason my code is skipping a line after every list item. I checked the code with the one of Dave's in the video but I can`t find whats wrong.

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 ulist = "<ol>";
  for (var i=0; i < list.length; i += 1){
    ulist += "<li>" + list[i] + "<li>";
}
  ulist += "</ol>";
  print(ulist);
}
printList(playList);

Moderator Edit: Corrected Markdown so the code block is readable in the Community. Please refer to the Markdown Cheatsheet (located above the Post tab), or have a look at the Markdown Basics course here on Treehouse.

3 Answers

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

I notice that the ending tag for the list items is missing a slash:

 ulist += "<li>" + list[i] + "<li>";   // original
 ulist += "<li>" + list[i] + "</li>";  // fixed

The extra starting tag created an empty list item after each intended one.

For future issues, you can use the snapshot function in the workspace and provide the link to it to facilitate a complete analysis while saving posting space and providing code with original formatting.

Stefan Cutajar
Stefan Cutajar
7,747 Points
Stefan Cutajar
Stefan Cutajar
7,747 Points

Thanks I did not catch that. I tried to write it again but this time nothing shows can you take a look for me please? https://w.trhou.se/s2cyt7bzbe

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

This time it's the spelling of "lentgh" instead of "length" on line 16.

Stefan Cutajar
Stefan Cutajar
7,747 Points
Stefan Cutajar
Stefan Cutajar
7,747 Points

Thanks a lot :D Any idea of how can I debug in similar cases like this because there wasn't any information given in the console.

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

In this case the best tool is the "calibrated eyeball" :eyes: since an undefined property is simply "undefined" and not an error.

There might be some other code-checking tools that would detect it but I tried this in my favorite (JsHint) and it also did not show it as an error.

Stefan Cutajar
Stefan Cutajar
7,747 Points
Stefan Cutajar
Stefan Cutajar
7,747 Points

Thanks I didn't know about JsHint I think it maybe introduced later in the course it looks like a good tool when debugging :)