Question

Possible Duplicate:
Why does !new Boolean(false) equals false in JavaScript?

var b = new Boolean(null);


alert(b instanceof Boolean);

 if(b) {
    alert('cv');
    alert(b.toString());
 }

Why if code block is executed? Is b supposed to be a boolean type and evaluated as false?

Please explain thanks

Answer 1

All objects are truthy, except null. Therefore, even if you write new Boolean(false) specifically, it will still be truthy.

This is why you never write new Boolean. To cast to a boolean, just use !!