Module talk:Citation/CS1

Lua error in Module:Citation/CS1/Identifiers at line 1014: attempt to compare nil with number., Wikidata Q36472504

@Evolution and evolvability: The References section of Research, Education and Economic Growth currently contains 8 Wikidata references, one of which produces the following error:

• Lua error in Module:Citation/CS1/Identifiers at line 1014: attempt to compare nil with number., Wikidata Q36472504

• James Heckman; Seong Hyeok Moon; Rodrigo Pinto; Peter Savelyev; Adam Yavitz (1 January 2010). "Analyzing social experiments as implemented: A reexamination of the evidence from the HighScope Perry Preschool Program". Quantitative Economics 1 (1): 1-46. doi:10.3982/QE8. Wikidata Q36472504. ISSN 1759-7323. PMID 23255883. PMC 3524308. //www.ncbi.nlm.nih.gov/pmc/articles/PMC3524308/. 

The other 7 work find. I asked about this on Wikidata:Project chat#Wikiversity: Lua error in Module:Citation/CS1/Identifiers at line 1014: attempt to compare nil with number., Wikidata Q36472504 and got the following suggestions:

Module:Citation/CS1 here came from w:Module:Citation/CS1 in 2018. Supposedly that is the master copy. Testing there, it works too.

Maybe a new import from w: is needed at wikiversity. In any case, Module:Citation/CS1 doesn't seem to be maintained here. --- Jura 07:34, 19 August 2020 (UTC)

Some configuration (namely a "handler for PMC") is missing or not properly set on Wikiversity. This should help you if you seek help from the authors of the modules. --Matěj Suchánek (discuss) 07:56, 19 August 2020 (UTC)

Might you be able to fix this? Thanks, DavidMCEddy (discuss • contribs) 13:48, 19 August 2020 (UTC)

@Matěj Suchánek: Thanks for the suggestion. How can I find the authors of the modules? DavidMCEddy (discuss • contribs) 03:27, 23 August 2020 (UTC)

It looks quite complex to trace. The lua error is raised from Module:Citation/CS1/Identifiers, a submodule of Module:Citation/CS1, which per its history here was imported from enwiki. So posting on its enwiki's talk page can be the place to ask for help.

Anyway, another look into this lead me to Module:Citation/CS1/Configuration, specifically to 'PMC' (line 1560), where the field id_limit is expected but is missing. I have no idea what value for it is appropriate, though. --Matěj Suchánek (discuss • contribs) 18:38, 23 August 2020 (UTC)

Thanks. I posted essentially this question to Module talk:Citation/CS1/Identifiers, pinging a couple of people listed in "history" for that page. DavidMCEddy (discuss • contribs) 20:00, 23 August 2020 (UTC)