xmonad-0.9.2: A tiling window manager

Portability
Stabilityprovisional
MaintainerDon Stewart <dons@galois.com>

XMonad

Description

 

Synopsis

Documentation

(.|.) :: Bits a => a -> a -> a

Bitwise "or"

class Monad m => MonadState s m | m -> s where

Methods

get :: m s

Return the state from the internals of the monad.

put :: s -> m ()

Replace the state inside the monad.

gets :: MonadState s m => (s -> a) -> m a

Gets specific component of the state, using a projection function supplied.

modify :: MonadState s m => (s -> s) -> m ()

Monadic state transformer.

Maps an old state to a new state inside a state monad. The old state is thrown away.

      Main> :t modify ((+1) :: Int -> Int)
      modify (...) :: (MonadState Int a) => a ()

This says that modify (+1) acts over any Monad that is a member of the MonadState class, with an Int state.

class Monad m => MonadReader r m | m -> r where

See examples in Control.Monad.Reader. Note, the partially applied function type (->) r is a simple reader monad. See the instance declaration below.

Methods

ask :: m r

Retrieves the monad environment.

local

Arguments

:: (r -> r)

The function to modify the environment.

-> m a

Reader to run in the modified environment.

-> m a 

Executes a computation in a modified environment.

asks

Arguments

:: MonadReader r m 
=> (r -> a)

The selector function to apply to the environment.

-> m a 

Retrieves a function of the current environment.

class Monad m => MonadIO m where

Methods

liftIO :: IO a -> m a