Hoogle Search

Within LTS Haskell 24.60 (ghc-9.10.3)

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

Exact lookup

1. lookup :: (Monad m, Eq a) => a -> SerialT m (a, b) -> m (Maybe b)

   streamly	Streamly.Prelude

   In a stream of (key-value) pairs (a, b), return the value b of the first pair where the key equals the given value a.

   lookup = snd <$> Stream.find ((==) . fst)
   lookup = Stream.fold Fold.lookup
   

2. lookup :: (Textual str, MonadIO m) => str -> m (Maybe Symbol)

   symbolize	Symbolize

   Looks up a symbol in the global symbol table. Returns Nothing if no such symbol currently exists. First converts the string to a ShortText (if it isn't already one). See Textual for the type-specific time complexity of this. Then, takes O(min(n, 64)) time, where n is the number of symbols currently in the table. Runs concurrently with any other operation on the symbol table, without any atomic memory barriers. Because the result can vary depending on the current state of the symbol table, this function is not pure.

3. lookup :: Coupon -> Vendor a -> IO (Maybe (RemotePtr a))

   threepenny-gui	Foreign.RemotePtr

   Take a Coupon to a Vendor and maybe you'll get a RemotePtr for it.

4. lookup :: Ord k => TMapMVar k a -> k -> STM a

   tmapmvar	Control.Concurrent.STM.TMapMVar

   Blocks, and deletes upon looking it up

5. lookup :: (Eq k, Hashable k) => TMapMVar k a -> k -> STM a

   tmapmvar	Control.Concurrent.STM.TMapMVar.Hash

   Blocks, and deletes upon looking it up

6. lookup :: Key -> PrefixMap a -> Maybe a

   tomland	Toml.Type.PrefixTree

   Looks up the value at a key in the PrefixMap.

7. lookup :: Ord c => [c] -> TMap c a -> Maybe a

   trie-simple	Data.Trie.Map

   lookup xs tmap returns Just a if tmap contains mapping from xs to a, and returns Nothing if not.

8. lookup :: (Eq k, Hashable k) => k -> Map k v -> STM (Maybe v)

   ttrie	Control.Concurrent.STM.Map

   O(log n). Return the value associated with the given key, or Nothing. Note: This might increase the map's memory consumption by putting the key into the map. If that is not acceptable, use phantomLookup.

9. lookup :: forall t x proxy . Typeable t => proxy t -> TypeMap x -> Maybe (Item x t)

   type-map	Data.TypeMap.Dynamic

   Lookup an element indexed by type t.

10. lookup :: Typeable t => TypeMap x -> Maybe (Item x t)

    type-map	Data.TypeMap.Dynamic.Alt

    Lookup an element indexed by type t.

Page 23 of many | Previous | Next