Lua/Template integrations

[DavidVentura]

Hi
I'm trying to understand how wiktextract executes the templates/Lua modules that are used by Wiktionary, and how are the modules/templates tar files generated.

As an example, given the dog en.wiktionary entry:

** {{IPA|en|/dɑɡ/|a=cot-caught}}

where is IPA defined? how does wiktionary 'render'/'execute' the template/script?

[xxyzz]

Template data are downloaded from Wikimedia dump file, template expansion and executing Lua code is implemented in wikitextprocessor(please see luaexec.py and the lua folder).

[kristian-clausal]

The wikitext {{IPA|...}} is expanded by 'calling' the Template:IPA page. The page contains template text that receives parameters from the template call and it can contain control flow structures like {{#if:...}} which lets you program some simple things, or complex things if you want to create unreadable monster code.

Lua functions calls are different, they are done with {{#invoke:...}} which calls a Module: page with Lua code that is excecuted. Check out Wikipedia:Lua for more.

As for wikitextprocessor (which is what actually does the work here, check out that repo), what it does is two things: 1) parse a wikitext into a parse tree (which is often broken because wikitext is not actually 'parsable' this way because templates and lua code can generate more wikitext) and 2) do what Wikitext is meant to do and expand template calls (including parser functions like #if) and run Lua code in #invoke calls.