[beernutz]

I like a LOT of these comments, but some just leave me scratching my head:

// bad void function() { /* IIFE / }();

// good (function() { / IIFE */ }());

To me, the "bad" one was more readable until I noticed you were invoking the function. Personally, I don't like either notation, but the point is that this example (along with quite a few others) seems to need more explanation to get the point across.

I would maybe think about defining "IIFE" as well as maybe sectioning off the more "functional programming" sections.

Thank you for taking the time to put this together.