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

Dos T
Dos T
2,522 Points
Posted by Dos T
Dos T
2,522 Points

Hi, I need a help!

I don't understand why we need a function " print(message) " and what we will write here , any text? But why we need it, how it will affect for our loop or Play List? And why in function printList, we added parametr list, and then when call a function printList we wrote in argument of printList "playList"? Why we didn't write from the begining in parametr -"playList", not "list" ?

1 Answer

edinjusupovic
edinjusupovic
5,664 Points
edinjusupovic
edinjusupovic
5,664 Points

The print() function is just a regular function that was created to make writing data to the document faster. So instead of using; 

document.write('<h1>Hello World</h1>')

We can use; 

var foo = '<h1>Hello World</h1>';
function print(foo) {
    document.write(foo);
};

So now anytime we wish to use document.write, we can use print(message-here) instead.

The print function also takes your message print(foo) and it uses what was passed to it, in this case, foo, and passes that to, in this case, document.write; which would then output the message into the document using the document.write functionality.

Additionally, the printList function is being passed the list (the list being playList); the thing to remember is that what you're passing to the function doesn't have to be the identifier itself. See; 

var foo = 'example data'; 

function print(message) { // the "message" is only what the function is using as a placeholder to later identify it inside the function 
    document.write(message); // see here we are now using message again, this is what we originally passed to the function
};

In the above example, we can pass anything to the function and it will replace the (message) in a sense and use it; the print(message) - message part is only a placeholder. You can pass print('Hello!') and it will work fine.