Of course. The ad_proc -callback definitions should be:
ad_proc -callback MergeShowUserInfo {
-user_id:required
} {
Show the items that user_id owns
} {}
ad_proc -callback MergePackageUser {
-from_user_id:required
-to_user_id:required
} {
Merge two accounts
} {}
>>ShowUserInfo will return a list of objects "owned" by a package by a user that will be handled by that package in the merge operation?
Yes, each implementation returns a list of items of its package owned or related with the user "to merge".
>>And will MergePackageUser then update the appropriate data in each package to update the user_ids for the merged user?
Yes, it'll do that.