When would this return FALSE?

[hmichaels]

Hi all,

I'm analysing some different scripts to learn more about JavaScript. One thing I've noticed in a few of them is the following piece of code:

if (document.getElementById && document.getElementsByTagName) {
   //stuff
   }

When would this ever return FALSE? As long as the page has tags, I can't see how this could return FALSE, so why include it in the first place when the script is event-driven?

[CommanderZ]

This should test if the DOM structure is completely loaded or not. It would return false in case the structure was incomplete yet.

[felgall]

It would return false if the person is using Internet Explorer 4, Netscape 4, or any other old browser that came out before those commands were introduced.