Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/prelude/PreludeList/Scanr.hs
module Prelude where scanr :: (a -> b -> b) -> b -> [a] -> [b] scanr f q0 [] = [q0] scanr f q0 (x:xs) = f x q : qs where qs@(q:_) = scanr f q0 xs
