Module:Change

Documentation for this module may be created at Module:Change/doc

local p = {}

function p.prefix(frame)
    local key = frame.args[1] or ""
    if key:sub(1, 4) == "item" then
        return key
    elseif key:sub(1, 5) == "token" then  -- fixed length: "token" is 5 characters
        return key
    elseif key:sub(1, 1) == "!" then
        return key
    else
        return "system." .. key
    end
end

return p