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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Adding Data to Arrays

nicolo orcine
nicolo orcine
3,138 Points

function parameter. I dont understand printList (list)

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

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

I dont understand where the (list) parameter of function printList came from.

2 Answers


When you declare a function you can define the number of parameters it has. You can name the parameters whatever you like, in this case the function has one parameter called 'list'.

When you use (or call) the function you provide the same number of arguments as the number of parameters you have defined previously, so this function here takes one argument. You pass it the playlist array and it loops through it, storing the result in a variable. After that the print function is called with this variable as an argument.

Hope this helps!