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1. idleTimeout :: RedisStorage sess -> Maybe NominalDiffTime

   serversession-backend-redis	Web.ServerSession.Backend.Redis

   How long should a session live after last access

2. idleTimeout :: RedisStorage sess -> Maybe NominalDiffTime

   serversession-backend-redis	Web.ServerSession.Backend.Redis.Internal

   How long should a session live after last access

3. identity :: a -> a

   verset	Verset

   The identity function, returns the give value unchanged.

4. idFadeHook :: FadeHook

   xmonad-contrib	XMonad.Hooks.FadeWindows

   The identity FadeHook, which renders windows opaque.

5. class Semigroup a => Monoid a

   base	Prelude

   The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:

   • Right identity x <> mempty = x
   • Left identity mempty <> x = x
   • Associativity x <> (y <> z) = (x <> y) <> z (Semigroup law)
   • Concatenation mconcat = foldr (<>) mempty
   You can alternatively define mconcat instead of mempty, in which case the laws are:
   • Unit mconcat (pure x) = x
   • Multiplication mconcat (join xss) = mconcat (fmap mconcat xss)
   • Subclass mconcat (toList xs) = sconcat xs
   The method names refer to the monoid of lists under concatenation, but there are many other instances. Some types can be viewed as a monoid in more than one way, e.g. both addition and multiplication on numbers. In such cases we often define newtypes and make those instances of Monoid, e.g. Sum and Product. NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.

6. void :: Functor f => f a -> f ()

   base	Control.Monad

   void value discards or ignores the result of evaluation, such as the return value of an IO action.

   Examples

   Replace the contents of a Maybe Int with unit:

   >>> void Nothing
   Nothing
   

   >>> void (Just 3)
   Just ()
   

   Replace the contents of an Either Int Int with unit, resulting in an Either Int ():

   >>> void (Left 8675309)
   Left 8675309
   

   >>> void (Right 8675309)
   Right ()
   

   Replace every element of a list with unit:

   >>> void [1,2,3]
   [(),(),()]
   

   Replace the second element of a pair with unit:

   >>> void (1,2)
   (1,())
   

   Discard the result of an IO action:

   >>> mapM print [1,2]
   1
   2
   [(),()]
   

   >>> void $ mapM print [1,2]
   1
   2
   

7. data ThreadId

   base	Control.Concurrent

   A ThreadId is an abstract type representing a handle to a thread. ThreadId is an instance of Eq, Ord and Show, where the Ord instance implements an arbitrary total ordering over ThreadIds. The Show instance lets you convert an arbitrary-valued ThreadId to string form; showing a ThreadId value is occasionally useful when debugging or diagnosing the behaviour of a concurrent program. Note: in GHC, if you have a ThreadId, you essentially have a pointer to the thread itself. This means the thread itself can't be garbage collected until you drop the ThreadId. This misfeature would be difficult to correct while continuing to support threadStatus.

8. mkWeakThreadId :: ThreadId -> IO (Weak ThreadId)

   base	Control.Concurrent

   Make a weak pointer to a ThreadId. It can be important to do this if you want to hold a reference to a ThreadId while still allowing the thread to receive the BlockedIndefinitely family of exceptions (e.g. BlockedIndefinitelyOnMVar). Holding a normal ThreadId reference will prevent the delivery of BlockedIndefinitely exceptions because the reference could be used as the target of throwTo at any time, which would unblock the thread. Holding a Weak ThreadId, on the other hand, will not prevent the thread from receiving BlockedIndefinitely exceptions. It is still possible to throw an exception to a Weak ThreadId, but the caller must use deRefWeak first to determine whether the thread still exists.

9. myThreadId :: IO ThreadId

   base	Control.Concurrent

   Returns the ThreadId of the calling thread (GHC only).

10. DivideByZero :: ArithException

    base	Control.Exception

    No documentation available.

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