/usr/share/doc/frown-doc/examples/manual/Result.lhs is in frown-doc 0.6.1-14.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | > module Result where
>
> data Result a = Return a | Fail String
> deriving (Show)
>
> instance Monad Result where
> return = Return
> Fail s >>= k = Fail s
> Return a >>= k = k a
> fail = Fail
|