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

Posted by nagamani palamuthi
nagamani palamuthi
6,160 Points

playlist code

https://w.trhou.se/f6zxc3x3l2

if i use (playlist) instead of (list), as an argument for function printList , is it wrong coding? I tried it and it works.

see code above.

1 Answer

Benjamin Barslev Nielsen
Benjamin Barslev Nielsen
18,958 Points
Benjamin Barslev Nielsen
Benjamin Barslev Nielsen
18,958 Points

Since you declare the variable name of your array to be playList:

var playList = ...;

you need to call 

printList(playList);

instead of using list. It would be wrong to write:

printList(list);

since you do not define a variable named list.

Aurelian Spodarec
Aurelian Spodarec
10,801 Points
Aurelian Spodarec
Aurelian Spodarec
10,801 Points

Where is the var playList? i don't see it anywhere in the code.

Stephen O'Dell
Stephen O'Dell
1,596 Points
Stephen O'Dell
Stephen O'Dell
1,596 Points

I don't think that's what nagamani was talking about. I think we're talking about the parameter of the function printList on line 14.

Dave's words, around 5:30: This function takes an array as a parameter. Remember, a parameter is a variable that holds some value that's passed to the function. We'll pass an array to this function, so I'll give the parameter a simple name, like list.

So, he gave it the simple name list, but never declared list to be a variable of any sort. Then two lines later, we're using list.length in our test condition. But the array is named playList, not list.

For this function, how do we know the length of "list"? I can't find where it's defined or declared anywhere.

'''javascript function printList ( list ) { var listHTML = '<ol>'; for ( var i = 0; i < list.length; i += 1 ) { listHTML += '<li>' + list[i] + '</li>'; } '''