WowAce

recently (maybe my Prat alts list is corrupted?) function lib:ListAlts started throwing a nil operator error on line 327, caused by an alt whose value is the empty string ""

2x AddOns\RosterTooltip\Libs\LibAlts-1.0\LibAlts-1.0-40.lua:327: attempt to index field '?' (a nil value)
Locals: nil

The existing sanity check traps nil assignments, but not the empty string "". Thus,

if not alt then return nil end

needs to be changed to

if not alt or alt == "" then return nil end

to resolve the issue.