| Portability | non-portable (multi-param classes, functional dependencies) |
|---|---|
| Stability | experimental |
| Maintainer | libraries@haskell.org |
Control.Monad.Writer.Strict
Description
Strict writer monads.
Inspired by the paper /Functional Programming with Overloading and Higher-Order Polymorphism/, Mark P Jones (http://web.cecs.pdx.edu/~mpj/pubs/springschool.html) Advanced School of Functional Programming, 1995.
Documentation
module Control.Monad.Writer.Class
execWriter :: Writer w a -> wSource
Constructors
| WriterT | |
Fields
| |
Instances
| (Monoid w, Monad m) => MonadWriter w (WriterT w m) | |
| (Monoid w, MonadError e m) => MonadError e (WriterT w m) | |
| (Monoid w, MonadState s m) => MonadState s (WriterT w m) | |
| (Monoid w, MonadReader r m) => MonadReader r (WriterT w m) | |
| Monoid w => MonadTrans (WriterT w) | |
| (Monoid w, Monad m) => Monad (WriterT w m) | |
| Monad m => Functor (WriterT w m) | |
| (Monoid w, MonadFix m) => MonadFix (WriterT w m) | |
| (Monoid w, MonadPlus m) => MonadPlus (WriterT w m) | |
| (Monoid w, MonadIO m) => MonadIO (WriterT w m) | |
| (Monoid w, MonadCont m) => MonadCont (WriterT w m) |
execWriterT :: Monad m => WriterT w m a -> m wSource
mapWriterT :: (m (a, w) -> n (b, w')) -> WriterT w m a -> WriterT w' n bSource
module Control.Monad
module Control.Monad.Fix
module Control.Monad.Trans
module Data.Monoid