Necessary Extension Missing for 10.2

[JonathanLorimer]

Need to add {-# LANGUAGE TypeOperators #-} to the necessary extensions at the beginning of 10.2 on pg. 126.

Everything works fine except for MapList pg. 129 and Foldr pg. 130 which depend on a promoted cons operator ': for example:

data FoldR :: (a -> b -> Exp b) -> b -> [a] -> Exp b
type instance Eval' (FoldR _ z '[]) = z
type instance Eval' (FoldR f z (x ': xs)) =
  Eval' (f x (Eval' (FoldR f z xs)))

I would create a PR myself, but I can't figure out how your TeX preamble is pulling code from your Haskell files