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Diffstat (limited to '')
-rw-r--r-- | Invisible.hs | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/Invisible.hs b/Invisible.hs index 5d040f7..8a5295c 100644 --- a/Invisible.hs +++ b/Invisible.hs @@ -33,6 +33,7 @@ instance Monad m => Show (Invisible m a) where instance (Functor m, Monad m) => Monad (Invisible m) where return a = I (return a) m >>= f = m >>= f + fail s = I (fail s) instance (Functor m, Monad m) => Functor (Invisible m) where fmap f (I x) = I (fmap f x) |