**scanr** -bytestring -containers

scanr is the right-to-left dual of scanl. Note that
> head (scanr f z xs) == foldr f z xs.
*O(n)* scanr is the right-to-left dual of scanl. Performs replacement on invalid scalar values.
> scanr f v == reverse . scanl (flip f) v . reverse
scanr1 is a variant of scanr that has no starting value argument.
*O(n)* scanr1 is a variant of scanr that has no starting value argument. Performs replacement on invalid scalar values.
*O(n)* scanr1 is a variant of scanr that has no starting value argument. Subject to fusion. Performs replacement on invalid scalar values.