refactoring

util/filter.lua

@@ -239,6 +239,7 @@ do
 			) do
 				if not self[parser[1]] then
 					tinsert(parser, str)
+					p(str, p(unpack(parser)), p(select(3, unpack(parser))))
 					local index, label = parser[2](select(3, unpack(parser)))
 					if index then
 						self[parser[1]] = A(label, index)

util/info.lua

@@ -372,7 +372,7 @@ end
 
 function public.item_class_index(item_class)
     for i, class in temp-A(GetAuctionItemClasses()) do
-	    if item_class == nil then error() end
+	    if type(item_class) ~= 'string' then error() end
         if strupper(class) == strupper(item_class) then
             return i, class
         end