Hoogle Search

Within LTS Haskell 24.51 (ghc-9.10.3)

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

Exact lookup

1. (.:) :: (c -> d) -> (a -> b -> c) -> a -> b -> d

   composition	Data.Composition

   Compose two functions. f .: g is similar to f . g except that g will be fed two arguments instead of one before handing its result to f. This function is defined as

   (f .: g) x y = f (g x y)
   

   Example usage:

   concatMap :: (a -> [b]) -> [a] -> [b]
   concatMap = concat .: map
   

   Notice how two arguments (the function and the list) will be given to map before the result is passed to concat. This is equivalent to:

   concatMap f xs = concat (map f xs)
   

2. (.:.) :: (d -> e) -> (a -> b -> c -> d) -> a -> b -> c -> e

   composition	Data.Composition

   One compact pattern for composition operators is to "count the dots after the first one", which begins with the common .:, and proceeds by first appending another . and then replacing it with :

3. (.::) :: (d -> e) -> (a1 -> a2 -> b -> c -> d) -> a1 -> a2 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

4. (.::.) :: (d -> e) -> (a1 -> a2 -> a3 -> b -> c -> d) -> a1 -> a2 -> a3 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

5. (.:::) :: (d -> e) -> (a1 -> a2 -> a3 -> a4 -> b -> c -> d) -> a1 -> a2 -> a3 -> a4 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

6. (.:::.) :: (d -> e) -> (a1 -> a2 -> a3 -> a4 -> a5 -> b -> c -> d) -> a1 -> a2 -> a3 -> a4 -> a5 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

7. (.::::) :: (d -> e) -> (a1 -> a2 -> a3 -> a4 -> a5 -> a6 -> b -> c -> d) -> a1 -> a2 -> a3 -> a4 -> a5 -> a6 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

8. (.::::.) :: (d -> e) -> (a1 -> a2 -> a3 -> a4 -> a5 -> a6 -> a7 -> b -> c -> d) -> a1 -> a2 -> a3 -> a4 -> a5 -> a6 -> a7 -> b -> c -> e

   composition	Data.Composition

   No documentation available.

9. (.|) :: forall (m :: Type -> Type) a b u v c r . Monad m => Pipe a b u m v -> Pipe b c v m r -> Pipe a c u m r

   conduino	Data.Conduino

   The main operator for chaining pipes together. pipe1 .| pipe2 will connect the output of pipe1 to the input of pipe2. Running a pipe will draw from pipe2, and if pipe2 ever asks for input (with await or something similar), it will block until pipe1 outputs something (or signals termination). The structure of a full pipeline usually looks like:

   runPipe $ someSource
   .| somePipe
   .| someOtherPipe
   .| someSink
   

   Where you route a source into a series of pipes, which eventually ends up at a sink. runPipe will then produce the result of that sink.

10. (.::) :: (Alternative f, Applicative f) => Lens' a b -> f b -> f (a -> a)

    configuration-tools	Configuration.Utils.CommandLine

    An operator for applying a setter to an option parser that yields a value. Example usage:

    data Auth = Auth
    { _user ∷ !String
    , _pwd ∷ !String
    }
    
    user ∷ Functor f ⇒ (String → f String) → Auth → f Auth
    user f s = (\u → s { _user = u }) <$> f (_user s)
    
    pwd ∷ Functor f ⇒ (String → f String) → Auth → f Auth
    pwd f s = (\p → s { _pwd = p }) <$> f (_pwd s)
    
    -- or with lenses and TemplateHaskell just:
    -- $(makeLenses ''Auth)
    
    pAuth ∷ MParser Auth
    pAuth = id
    <$< user .:: strOption
    % long "user"
    ⊕ short 'u'
    ⊕ help "user name"
    <*< pwd .:: strOption
    % long "pwd"
    ⊕ help "password for user"
    

Page 57 of many | Previous | Next