Board Thread:Watercooler/@comment-5590118-20150701035141/@comment-11733175-20150709122521

Your link doesn't say any lua implementation of string functions is more efficient than parser functions it just describes the results of a test using lua's string functions. You can't make those claims without running similar tests with both implementations. In addition, that section does not note how inefficient lua is at creating strings, which is something worth considering when working with multiple strings.

However, the fact that wikipedia has a module to replace the string function part of ParserFunctions may lend credence to your statement of effieciency. It does not give any credence to any module that implements #if, #switch or any other parser function directly, as scribunto is designed to replace the use of parser function logic within templates not to replace parser functions with #invoke which are then used for template logic again. Aside from performance concerns, you're actually making the mess of logic in wikitext worse.