Safe Haskell | None |
---|---|
Language | Haskell98 |
Overloaded null
and empty
for collections and sequences.
- class Null a where
- ifNull :: Null a => a -> b -> (a -> b) -> b
- ifNullM :: (Monad m, Null a) => m a -> m b -> (a -> m b) -> m b
- whenNull :: (Monad m, Null a) => a -> m () -> m ()
- unlessNull :: (Monad m, Null a) => a -> (a -> m ()) -> m ()
- whenNullM :: (Monad m, Null a) => m a -> m () -> m ()
- unlessNullM :: (Monad m, Null a) => m a -> (a -> m ()) -> m ()
Documentation
Null () Source | |
Null ByteString Source | |
Null IntSet Source | |
Null Permutation Source | |
Null ClauseBody Source | |
Null Clause Source | A |
Null Simplification Source | |
Null Fields Source | |
Null ProblemRest Source | |
Null [a] Source | |
Null (Maybe a) Source | |
Null (IntMap a) Source | |
Null (Set a) Source | |
Null (Seq a) Source | |
Null (Bag a) Source | |
Null a => Null (SizedThing a) Source | |
Null (Favorites a) Source | |
Null (CMSet cinfo) Source | |
Null (CallGraph cinfo) Source |
|
Null (Range' a) Source | |
Null (Tele a) Source | |
Null (Match a) Source | |
Null a => Null (Problem' a) Source | |
(Null a, Null b) => Null (a, b) Source | |
Null (Map k a) Source |
Testing for null.
unlessNull :: (Monad m, Null a) => a -> (a -> m ()) -> m () Source
unlessNullM :: (Monad m, Null a) => m a -> (a -> m ()) -> m () Source