The answer to your question is "Not really that big": 3.5kloc with comments/whitespace and 1.6kloc without.
Your point is valid that much of this is the library's doing, but I think more of the difference than you're letting on is just from how well-suited functional languages are to this sort of work compared to dynamic scripting languages. Parsec is practically a Haskell standard library, anyway; I wouldn't discount it any more than I would discount using Node's buffer or stream module.
