Objective
To practice with constructor functions, objects, and methods
Instructions
The code shown in the head section below is incomplete. You will need to complete the code in the head section by finishing the Number constructor function and adding methods to it so that the code in the body will execute without errors and will produce the output specified in the comments.
Incomplete Code
<!DOCTYPE html>
<head>
<meta charset="utf-8">
<title>Number Methods</title>
<meta name="viewport" content="width=device-width">
<script type="text/javascript">
function Number( value ) {
}
</script>
</head>
<body>
<h1>Number Methods</h1>
<script type="text/javascript">
var num1 = new Number( 3 );
var num2 = new Number( 9 );
// should output "num1 is: 3<br/>"
document.writeln( "num1 is: " + num1.value + "<br/>" );
// should output "num2 is: 9<br/>"
document.writeln( "num2 is: " + num2.value + "<br/>" );
// should output "num1 + num2 is: 12<br/>"
document.writeln( "num1 + num2 is: " + num1.add( num2 ) + "<br/>" );
// should output "num2 - num1 is: 6<br/>"
document.writeln( "num2 - num1 is: " + num2.subtract( num1 ) + "<br/>" );
</script>
</body>
</html>