[unit : All x. x -> List x,
 append : All x. List x -> List x -> List x,
 fix : All x. (x -> x) -> x]
? \x. x : a0 -> a0
? \x y. x : a0 -> a1 -> a0
? Failed to parse
? Failed to type
? \f g x. g (f x) : (a2 -> a3) -> (a3 -> a4) -> a2 -> a4
? Failed to type
? (\x. x) (\x. x) : a1 -> a1
? Failed to type
? let  id = (\x. x)  in  id id : a2 -> a2
? Failed to type
? fix (\x. x) : a2
? Failed to type
? \x. unit (unit x) : a0 -> List (List a0)
? Failed to type
? \x. fix (\xs. append (unit x) xs) : a0 -> List a0
? let  id = (\x. x)  in  id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id id : a566 -> a566
?