if ($is_front) { }
global $user; if ($user->uid > 0) { }
Ah yes -- but you see this is a theme that I intend to release publically, so I have to use non-site-specific variables (e.g. the navigation block appearing on the left only for users).
Why are these variables site specific? $is_front is created by PHPTemplate, and I don't have to tell you where $user comes from.
Are you trying to define a "region"? 4.7 has these. Your theme could define a bunch of different regions and you could test
If ($region1) {} If ($region2) {} ... Etc
I guess I'm not understanding the problem.
-M