modules/renumber: check config value more properly

diff --git a/modules/renumber/renumber.lua b/modules/renumber/renumber.lua
index 88c60bc010a32b560de95c7e428140e3e00e53e3..17fb302d472ea5fb8a27eab49c98d6ecc108404c 100644 (file)
--- a/modules/renumber/renumber.lua
+++ b/modules/renumber/renumber.lua
@@ -40,7 +40,9 @@ end
 -- Config
 function mod.config (conf)
        if conf == nil then return end
-       if type(conf) ~= 'table' then error('[renumber] expected { {prefix, target}, ... }') end
+       if type(conf) ~= 'table' or type(conf[1]) ~= 'table' then
+               error('[renumber] expected { {prefix, target}, ... }')
+       end
        for i = 1, #conf do add_prefix(conf[i][1], conf[1][2]) end
 end
 -- Layers