Joomla 3.0 DS does not work. It has been removed. I get
Notice: Use of undefined constant DS - assumed 'DS' in
How can I fix this?
Add the below line
if(!defined('DS')) define('DS', DIRECTORY_SEPARATOR);
From the docs.
The DS constant has been removed. If you really need it you can use
Also there is a plugin to fix this issue.
You can find the full list here.
Sometimes you need this:
if(!defined('DS')) define('DS', '/');