CB

I don't like applying the array case on the fallbacks for old implementations.

Correct fix would be to fix the gid field-type to provide a proper getField() method ?

gid doesn't exist as a field, it's a part of userparams so you can't use getField on it without basically adding a new system calculated field to CB that provides just gid. Regardless though user variables returning arrays still needs to be handled for the substitution usage; don't have any other solution to propose without having to completely add a new field.

Actually, what would work much better is a specific IF on a View Access Level for the IF in substitutions. Testing on groups is nice too, but less useful.

Using groups directly is not the recommended way (except for assigning users to groups).

I would stick with viewaccesslevel="2"

Which is enough for all cases. It's easy to add access levels as required, and it's the standard way for viewing permissions.

For action permissions, you would need to use something like [IF authorize="action,asset"]. But:
1) Joomla doesn't yet have a way to define and manage user-defined assets and actions on them.
2) assets are mostly for backend for now

So groups and action authorizations should be postponed to after CB 2.0 imho.

For "viewaccesslevel" (trying to keep terminology) you are welcome to submit a patch.
For "gid" if you add a type at top of the cb.core.php file array, it can return a properly formatted, comma-separated string. But that is not required imho.

Proposed patch just adds a check to see if the field is "viewaccesslevel" and if it is to parse the users view levels into |*| delimitered string. It could actually be moved further down as an ifelse to if ( isset( $user->_cbuser->$fieldLower ) ) {, but seams un-necessary to go through all that API first for viewaccesslevel.

Fixed in r1752 .