Lua templating; module:fallback indexing a null value errors. - Wikitech-l

7 Mar 2015

Hi,

On my local Wiki (i.e., @localhost) I have Scribunto installed, and I 
have copied several templates from Wikimedia Commons including 
Template:Derivative versions 
<https://commons.wikimedia.org/wiki/Template:Derivative_versions>, 
Template:Autotranslate 
<https://commons.wikimedia.org/wiki/Template:Autotranslate> and its Lua 
dependency, Module:Fallback 
<https://commons.wikimedia.org/wiki/Module:Fallback>. On my Wiki the 
Template:Derivative versions page, is giving the script error:

    Lua error in Module:Fallback at line 73: attempt to index a nil value.

    Backtrace:

     1. *(tail call)*: ?
     2. *Module:Fallback:73

<http://localhost/mediawiki/index.php?title=Module:Fallback&action=edit#mw-ce-l73>*:
        in function "fallbackpage"
     3. *Module:Fallback:99

<http://localhost/mediawiki/index.php?title=Module:Fallback&action=edit#mw-ce-l99>*:
        in function "chunk"
     4. *mw.lua:497*: ?
     5. *(tail call)*: ?
     6. *[C]*: in function "xpcall"
     7. *MWServer.lua:87*: in function "handleCall"
     8. *MWServer.lua:301*: in function "dispatch"
     9. *MWServer.lua:40*: in function "execute"
    10. *mw_main.lua:7*: in main chunk
    11. *[C]*: ?

Thanks for your time,
Brenton