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1. forever :: Applicative f => f a -> f b

   turtle	Turtle

   Repeat an action indefinitely.

   Examples

   A common use of forever is to process input from network sockets, Handles, and channels (e.g. MVar and Chan). For example, here is how we might implement an echo server, using forever both to listen for client connections on a network socket and to echo client input on client connection handles:

   echoServer :: Socket -> IO ()
   echoServer socket = forever $ do
   client <- accept socket
   forkFinally (echo client) (\_ -> hClose client)
   where
   echo :: Handle -> IO ()
   echo client = forever $
   hGetLine client >>= hPutStrLn client
   

   Note that "forever" isn't necessarily non-terminating. If the action is in a MonadPlus and short-circuits after some number of iterations. then forever actually returns mzero, effectively short-circuiting its caller.

2. format :: Format Text r -> r

   turtle	Turtle.Format

   Convert a Format string to a print function that takes zero or more typed arguments and returns a Text string

3. fork :: MonadManaged managed => IO a -> managed (Async a)

   turtle	Turtle.Prelude

   Fork a thread, acquiring an Async value

4. foreignPtrToPtr :: ForeignPtr a -> Ptr a

   unsafe	System.Unsafe

   No documentation available.

5. formDataFiles :: FormDataResult a -> [File a]

   webgear-core	WebGear.Core.MIMETypes

   No documentation available.

6. formDataParams :: FormDataResult a -> [Param]

   webgear-core	WebGear.Core.MIMETypes

   No documentation available.

7. forbidden403 :: Set h Status => h () (With Response '[Status])

   webgear-core	WebGear.Core.Trait.Status

   Forbidden 403 response

8. forestGreen :: Color (SRGB 'NonLinear) Word8

   Color	Graphics.Color.Standard.SVG

   Defined in SVG1.1 as

   forestgreen = rgb(34, 139, 34)
   

   Example

   >>> import Codec.Picture as JP
   
   >>> import Codec.Picture.Png (writePng)
   
   >>> let ColorSRGB r g b = forestGreen
   
   >>> let img = JP.generateImage (\_ _ -> JP.PixelRGB8 r g b) 200 34
   
   >>> writePng "files/svg/ForestGreen.png" img
   

9. forever :: forall (m :: Type -> Type) a b e . Monad m => AutomatonExcept a b m e -> Automaton m a b

   automaton	Data.Automaton.Trans.Except

   No documentation available.

10. foreverExcept :: forall (m :: Type -> Type) e a . (Functor m, Monad m) => StreamT (ExceptT e m) a -> StreamT m a

    automaton	Data.Stream

    Execute the stream until it throws an exception, then restart it. One might be tempted to define this function recursively with applyExcept, but this would result in a runtime error, trying to define an infinite state.

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