Bricks.Internal.Monad

IO

class Monad m => MonadIO (m :: * -> *) where

Monads in which IO computations may be embedded. Any monad built by applying a sequence of monad transformers to the IO monad will be an instance of this class.

Instances should satisfy the following laws, which state that liftIO is a transformer of monads:

• liftIO . return = return

• liftIO (m >>= f) = liftIO m >>= (liftIO . f)

Minimal complete definition

liftIO

Methods

liftIO :: IO a -> m a

Lift a computation from the IO monad.

Instances

MonadIO IO

Since: 4.9.0.0

Methods

liftIO :: IO a -> IO a

MonadIO Eval

Methods

liftIO :: IO a -> Eval a

MonadIO m => MonadIO (ListT m)

Methods

liftIO :: IO a -> ListT m a

MonadIO m => MonadIO (MaybeT m)

Methods

liftIO :: IO a -> MaybeT m a

(Error e, MonadIO m) => MonadIO (ErrorT e m)

Methods

liftIO :: IO a -> ErrorT e m a

MonadIO m => MonadIO (ExceptT e m)

Methods

liftIO :: IO a -> ExceptT e m a

MonadIO m => MonadIO (StateT s m)

Methods

liftIO :: IO a -> StateT s m a

MonadIO m => MonadIO (StateT s m)

Methods

liftIO :: IO a -> StateT s m a

(Monoid w, MonadIO m) => MonadIO (WriterT w m)

Methods

liftIO :: IO a -> WriterT w m a

(Monoid w, MonadIO m) => MonadIO (WriterT w m)

Methods

liftIO :: IO a -> WriterT w m a

MonadIO m => MonadIO (IdentityT * m)

Methods

liftIO :: IO a -> IdentityT * m a

MonadIO m => MonadIO (ReaderT * r m)

Methods

liftIO :: IO a -> ReaderT * r m a

MonadIO m => MonadIO (ParsecT s u m)

Methods

liftIO :: IO a -> ParsecT s u m a

(Monoid w, MonadIO m) => MonadIO (RWST r w s m)

Methods

liftIO :: IO a -> RWST r w s m a

(Monoid w, MonadIO m) => MonadIO (RWST r w s m)

Methods

liftIO :: IO a -> RWST r w s m a

Error

class Monad m => MonadError e (m :: * -> *) | m -> e where

The strategy of combining computations that can throw exceptions by bypassing bound functions from the point an exception is thrown to the point that it is handled.

Is parameterized over the type of error information and the monad type constructor. It is common to use Either String as the monad type constructor for an error monad in which error descriptions take the form of strings. In that case and many other common cases the resulting monad is already defined as an instance of the MonadError class. You can also define your own error type and/or use a monad type constructor other than Either String or Either IOError. In these cases you will have to explicitly define instances of the Error and/or MonadError classes.

Minimal complete definition

throwError, catchError

Methods

throwError :: e -> m a

Is used within a monadic computation to begin exception processing.

catchError :: m a -> (e -> m a) -> m a

A handler function to handle previous errors and return to normal execution. A common idiom is:

do { action1; action2; action3 } `catchError` handler

where the action functions can call throwError. Note that handler and the do-block must have the same return type.

Instances

MonadError IOException IO

Methods

throwError :: IOException -> IO a

catchError :: IO a -> (IOException -> IO a) -> IO a

MonadError Bottom Eval

Methods

throwError :: Bottom -> Eval a

catchError :: Eval a -> (Bottom -> Eval a) -> Eval a

MonadError e m => MonadError e (MaybeT m)

Methods

throwError :: e -> MaybeT m a

catchError :: MaybeT m a -> (e -> MaybeT m a) -> MaybeT m a

MonadError e m => MonadError e (ListT m)

Methods

throwError :: e -> ListT m a

catchError :: ListT m a -> (e -> ListT m a) -> ListT m a

MonadError e (Either e)

Methods

throwError :: e -> Either e a

catchError :: Either e a -> (e -> Either e a) -> Either e a

(Monoid w, MonadError e m) => MonadError e (WriterT w m)

Methods

throwError :: e -> WriterT w m a

catchError :: WriterT w m a -> (e -> WriterT w m a) -> WriterT w m a

(Monoid w, MonadError e m) => MonadError e (WriterT w m)

Methods

throwError :: e -> WriterT w m a

catchError :: WriterT w m a -> (e -> WriterT w m a) -> WriterT w m a

MonadError e m => MonadError e (StateT s m)

Methods

throwError :: e -> StateT s m a

catchError :: StateT s m a -> (e -> StateT s m a) -> StateT s m a

MonadError e m => MonadError e (StateT s m)

Methods

throwError :: e -> StateT s m a

catchError :: StateT s m a -> (e -> StateT s m a) -> StateT s m a

MonadError e m => MonadError e (IdentityT * m)

Methods

throwError :: e -> IdentityT * m a

catchError :: IdentityT * m a -> (e -> IdentityT * m a) -> IdentityT * m a

Monad m => MonadError e (ExceptT e m)

Methods

throwError :: e -> ExceptT e m a

catchError :: ExceptT e m a -> (e -> ExceptT e m a) -> ExceptT e m a

(Monad m, Error e) => MonadError e (ErrorT e m)

Methods

throwError :: e -> ErrorT e m a

catchError :: ErrorT e m a -> (e -> ErrorT e m a) -> ErrorT e m a

MonadError e m => MonadError e (ReaderT * r m)

Methods

throwError :: e -> ReaderT * r m a

catchError :: ReaderT * r m a -> (e -> ReaderT * r m a) -> ReaderT * r m a

MonadError e m => MonadError e (ParsecT s u m)

Methods

throwError :: e -> ParsecT s u m a

catchError :: ParsecT s u m a -> (e -> ParsecT s u m a) -> ParsecT s u m a

(Monoid w, MonadError e m) => MonadError e (RWST r w s m)

Methods

throwError :: e -> RWST r w s m a

catchError :: RWST r w s m a -> (e -> RWST r w s m a) -> RWST r w s m a

(Monoid w, MonadError e m) => MonadError e (RWST r w s m)

Methods

throwError :: e -> RWST r w s m a

catchError :: RWST r w s m a -> (e -> RWST r w s m a) -> RWST r w s m a

newtype ExceptT e (m :: * -> *) a :: * -> (* -> *) -> * -> *

A monad transformer that adds exceptions to other monads.

ExceptT constructs a monad parameterized over two things:

• e - The exception type.
• m - The inner monad.

The return function yields a computation that produces the given value, while >>= sequences two subcomputations, exiting on the first exception.

Constructors

ExceptT (m (Either e a))

Instances

Monad m => MonadError e (ExceptT e m)

Methods

throwError :: e -> ExceptT e m a

catchError :: ExceptT e m a -> (e -> ExceptT e m a) -> ExceptT e m a

MonadTrans (ExceptT e)

Methods

lift :: Monad m => m a -> ExceptT e m a

Monad m => Monad (ExceptT e m)

Methods

(>>=) :: ExceptT e m a -> (a -> ExceptT e m b) -> ExceptT e m b

(>>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b

return :: a -> ExceptT e m a

fail :: String -> ExceptT e m a

Functor m => Functor (ExceptT e m)

Methods

fmap :: (a -> b) -> ExceptT e m a -> ExceptT e m b

(<$) :: a -> ExceptT e m b -> ExceptT e m a

MonadFix m => MonadFix (ExceptT e m)

Methods

mfix :: (a -> ExceptT e m a) -> ExceptT e m a

MonadFail m => MonadFail (ExceptT e m)

Methods

fail :: String -> ExceptT e m a

(Functor m, Monad m) => Applicative (ExceptT e m)

Methods

pure :: a -> ExceptT e m a

(<*>) :: ExceptT e m (a -> b) -> ExceptT e m a -> ExceptT e m b

liftA2 :: (a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c

(*>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b

(<*) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m a

Foldable f => Foldable (ExceptT e f)

Methods

fold :: Monoid m => ExceptT e f m -> m

foldMap :: Monoid m => (a -> m) -> ExceptT e f a -> m

foldr :: (a -> b -> b) -> b -> ExceptT e f a -> b

foldr' :: (a -> b -> b) -> b -> ExceptT e f a -> b

foldl :: (b -> a -> b) -> b -> ExceptT e f a -> b

foldl' :: (b -> a -> b) -> b -> ExceptT e f a -> b

foldr1 :: (a -> a -> a) -> ExceptT e f a -> a

foldl1 :: (a -> a -> a) -> ExceptT e f a -> a

toList :: ExceptT e f a -> [a]

null :: ExceptT e f a -> Bool

length :: ExceptT e f a -> Int

elem :: Eq a => a -> ExceptT e f a -> Bool

maximum :: Ord a => ExceptT e f a -> a

minimum :: Ord a => ExceptT e f a -> a

sum :: Num a => ExceptT e f a -> a

product :: Num a => ExceptT e f a -> a

Traversable f => Traversable (ExceptT e f)

Methods

traverse :: Applicative f => (a -> f b) -> ExceptT e f a -> f (ExceptT e f b)

sequenceA :: Applicative f => ExceptT e f (f a) -> f (ExceptT e f a)

mapM :: Monad m => (a -> m b) -> ExceptT e f a -> m (ExceptT e f b)

sequence :: Monad m => ExceptT e f (m a) -> m (ExceptT e f a)

(Eq e, Eq1 m) => Eq1 (ExceptT e m)

Methods

liftEq :: (a -> b -> Bool) -> ExceptT e m a -> ExceptT e m b -> Bool

(Ord e, Ord1 m) => Ord1 (ExceptT e m)

Methods

liftCompare :: (a -> b -> Ordering) -> ExceptT e m a -> ExceptT e m b -> Ordering

(Read e, Read1 m) => Read1 (ExceptT e m)

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (ExceptT e m a)

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [ExceptT e m a]

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (ExceptT e m a)

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [ExceptT e m a]

(Show e, Show1 m) => Show1 (ExceptT e m)

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> ExceptT e m a -> ShowS

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [ExceptT e m a] -> ShowS

MonadZip m => MonadZip (ExceptT e m)

Methods

mzip :: ExceptT e m a -> ExceptT e m b -> ExceptT e m (a, b)

mzipWith :: (a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c

munzip :: ExceptT e m (a, b) -> (ExceptT e m a, ExceptT e m b)

MonadIO m => MonadIO (ExceptT e m)

Methods

liftIO :: IO a -> ExceptT e m a

(Functor m, Monad m, Monoid e) => Alternative (ExceptT e m)

Methods

empty :: ExceptT e m a

(<|>) :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a

some :: ExceptT e m a -> ExceptT e m [a]

many :: ExceptT e m a -> ExceptT e m [a]

(Monad m, Monoid e) => MonadPlus (ExceptT e m)

Methods

mzero :: ExceptT e m a

mplus :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a

(Eq e, Eq1 m, Eq a) => Eq (ExceptT e m a)

Methods

(==) :: ExceptT e m a -> ExceptT e m a -> Bool

(/=) :: ExceptT e m a -> ExceptT e m a -> Bool

(Ord e, Ord1 m, Ord a) => Ord (ExceptT e m a)

Methods

compare :: ExceptT e m a -> ExceptT e m a -> Ordering

(<) :: ExceptT e m a -> ExceptT e m a -> Bool

(<=) :: ExceptT e m a -> ExceptT e m a -> Bool

(>) :: ExceptT e m a -> ExceptT e m a -> Bool

(>=) :: ExceptT e m a -> ExceptT e m a -> Bool

max :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a

min :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a

(Read e, Read1 m, Read a) => Read (ExceptT e m a)

Methods

readsPrec :: Int -> ReadS (ExceptT e m a)

readList :: ReadS [ExceptT e m a]

readPrec :: ReadPrec (ExceptT e m a)

readListPrec :: ReadPrec [ExceptT e m a]

(Show e, Show1 m, Show a) => Show (ExceptT e m a)

Methods

showsPrec :: Int -> ExceptT e m a -> ShowS

show :: ExceptT e m a -> String

showList :: [ExceptT e m a] -> ShowS

runExceptT :: ExceptT e m a -> m (Either e a)

The inverse of ExceptT.

Reader

newtype ReaderT k r (m :: k -> *) (a :: k) :: forall k. * -> (k -> *) -> k -> *

The reader monad transformer, which adds a read-only environment to the given monad.

The return function ignores the environment, while >>= passes the inherited environment to both subcomputations.

Constructors

ReaderT

Fields

• runReaderT :: r -> m a

Instances

MonadError e m => MonadError e (ReaderT * r m)

Methods

throwError :: e -> ReaderT * r m a

catchError :: ReaderT * r m a -> (e -> ReaderT * r m a) -> ReaderT * r m a

MonadTrans (ReaderT * r)

Methods

lift :: Monad m => m a -> ReaderT * r m a

Monad m => Monad (ReaderT * r m)

Methods

(>>=) :: ReaderT * r m a -> (a -> ReaderT * r m b) -> ReaderT * r m b

(>>) :: ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m b

return :: a -> ReaderT * r m a

fail :: String -> ReaderT * r m a

Functor m => Functor (ReaderT * r m)

Methods

fmap :: (a -> b) -> ReaderT * r m a -> ReaderT * r m b

(<$) :: a -> ReaderT * r m b -> ReaderT * r m a

MonadFix m => MonadFix (ReaderT * r m)

Methods

mfix :: (a -> ReaderT * r m a) -> ReaderT * r m a

MonadFail m => MonadFail (ReaderT * r m)

Methods

fail :: String -> ReaderT * r m a

Applicative m => Applicative (ReaderT * r m)

Methods

pure :: a -> ReaderT * r m a

(<*>) :: ReaderT * r m (a -> b) -> ReaderT * r m a -> ReaderT * r m b

liftA2 :: (a -> b -> c) -> ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m c

(*>) :: ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m b

(<*) :: ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m a

MonadZip m => MonadZip (ReaderT * r m)

Methods

mzip :: ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m (a, b)

mzipWith :: (a -> b -> c) -> ReaderT * r m a -> ReaderT * r m b -> ReaderT * r m c

munzip :: ReaderT * r m (a, b) -> (ReaderT * r m a, ReaderT * r m b)

MonadIO m => MonadIO (ReaderT * r m)

Methods

liftIO :: IO a -> ReaderT * r m a

Alternative m => Alternative (ReaderT * r m)

Methods

empty :: ReaderT * r m a

(<|>) :: ReaderT * r m a -> ReaderT * r m a -> ReaderT * r m a

some :: ReaderT * r m a -> ReaderT * r m [a]

many :: ReaderT * r m a -> ReaderT * r m [a]

MonadPlus m => MonadPlus (ReaderT * r m)

Methods

mzero :: ReaderT * r m a

mplus :: ReaderT * r m a -> ReaderT * r m a -> ReaderT * r m a