> It seems rare to make use of the distinction between null and undefined in real Javascript code. It is admittedly rare, but when it's useful, it's _really_ u

> It seems rare to make use of the distinction between null and undefined in real Javascript code. It is admittedly rare, but when it's useful, it's _really_ useful. It can be used, e.g., to distinguish between "property is not set" and "property has been explicitly set to a non-value (null)". That's not _often_ useful, but when it is, it _really_ is. YMMV.