[circonian]

Originally Posted by SnowmanDK Follow up question: How do you know what return value is equal to what? I can't seem to find any tables showing that. As I can see 9 = ITEMTYPE_TOOL If I do a GetItemType(item.bag, item.slot) then I just get an integer.

You are correct there are several item types that are not used.
You can look on the wiki site under constants here: http://wiki.esoui.com/Constants_in_100008_API
and search for ITEMTYPE it will take you to a list that shows each item types values.

I don't remember for sure if that is a complete list, but you can create an up to date list by using the following code to grab all of the values of item types

-- Initialize ItemTypes
    local itemTypeTable = {}
    for key, value in zo_insecurePairs(_G) do
       if (key):find("ITEMTYPE_")  and type(value) == "number" then
          itemTypeTable [key] = value   -- sorts by itemType name
-- or reverse the key & value to sort them by number
          itemTypeTable [value ] = key-- sorts by itemType number
       end
    end

Props to Garkin for showing me this trick it has come in handy MANY times when I wanted to find all possible values of certain types of constants, or even to look for functions with certain words in them to see if a function existed for something I was trying to do (in case it was not listed on the wiki).