Control.Monad.Logger

A replacement for WriterT IO which uses mutable references.

Documentation

newtype Logger w a

A replacement for WriterT IO which uses mutable references.

Constructors

Logger

Fields

runLogger :: IORef w -> IO a

Instances

Monoid w => MonadWriter w (Logger w)

Monoid w => MonadBase IO (Logger w)

Monoid w => MonadBaseControl IO (Logger w)

Monoid w => Monad (Logger w)

Functor (Logger w)

Monoid w => Applicative (Logger w)

Monoid w => MonadIO (Logger w)

type StM (Logger w) a = a

runLogger' :: Monoid w => Logger w a -> IO (a, w)

Run a Logger computation, starting with an empty log.