Hoogle Search

Within LTS Haskell 24.34 (ghc-9.10.3)

Note that Stackage only displays results for the latest LTS and Nightly snapshot. Learn more.

Exact lookup

1. mapM :: (a -> IO b) -> InputStream a -> IO (InputStream b)

   io-streams	System.IO.Streams.Combinators

   Maps an impure function over an InputStream. mapM f s passes all output from s through the IO action f. Satisfies the following laws:

   Streams.mapM (f >=> g) === Streams.mapM f >=> Streams.mapM g
   Streams.mapM return === Streams.makeInputStream . Streams.read
   

2. mapM_ :: (a -> IO b) -> InputStream a -> IO (InputStream a)

   io-streams	System.IO.Streams.Combinators

   Maps a side effect over an InputStream. mapM_ f s produces a new input stream that passes all output from s through the side-effecting IO action f. Example:

   ghci> Streams.fromList [1,2,3] >>=
   Streams.mapM_ (putStrLn . show . (*2)) >>=
   Streams.toList
   2
   4
   6
   [1,2,3]
   

3. mapMaybe :: (a -> Maybe b) -> InputStream a -> IO (InputStream b)

   io-streams	System.IO.Streams.Combinators

   A version of map that discards elements mapMaybe f s passes all output from s through the function f and discards elements for which f s evaluates to Nothing. Example:

   ghci> Streams.fromList [Just 1, None, Just 3] >>=
   Streams.mapMaybe id >>=
   Streams.toList
   [1,3]
   

   Since: 1.2.1.0

4. mapMaybe :: (a -> Maybe b) -> [a] -> [b]

   strict	Data.Strict.Maybe

   Analogous to mapMaybe in Data.Maybe.

5. mapFromList :: IsMap map => [(ContainerKey map, MapValue map)] -> map

   mono-traversable	Data.Containers

   Convert a list of key-value pairs to a map

6. mapKeysWith :: (BiPolyMap map, BPMKeyConstraint map k1, BPMKeyConstraint map k2) => (v -> v -> v) -> (k1 -> k2) -> map k1 v -> map k2 v

   mono-traversable	Data.Containers

   No documentation available.

7. mapToList :: IsMap map => map -> [(ContainerKey map, MapValue map)]

   mono-traversable	Data.Containers

   Convert a map to a list of key-value pairs.

8. mapWithKey :: IsMap map => (ContainerKey map -> MapValue map -> MapValue map) -> map -> map

   mono-traversable	Data.Containers

   Apply a function over every key-value pair of a map.

9. mapM_ :: (MonoFoldable mono, Applicative m) => (Element mono -> m ()) -> mono -> m ()

   mono-traversable	Data.MonoTraversable.Unprefixed

   Synonym for omapM_

10. mapNonNull :: (Functor f, MonoFoldable (f b)) => (a -> b) -> NonNull (f a) -> NonNull (f b)

    mono-traversable	Data.NonNull

    fmap over the underlying container in a NonNull.

Page 161 of many | Previous | Next