Monad +Control -mtl

class Monad m
base Prelude, base Control.Monad, base Control.Monad.Instances
The Monad class defines the basic operations over a monad, a concept from a branch of mathematics known as category theory. From the perspective of a Haskell programmer, however, it is best to think of a monad as an abstract datatype of actions. Haskell's do expressions provide a convenient syntax for writing monadic expressions. Minimal complete definition: >>= and return. Instances of Monad should satisfy the following laws: > return a >>= k == k a > m >>= return == m > m >>= (\x -> k x >>= h) == (m >>= k) >>= h Instances of both Monad and Functor should additionally satisfy the law: > fmap f xs == xs >>= return . f The instances of Monad for lists, Data.Maybe.Maybe and System.IO.IO defined in the Prelude satisfy these laws.
module Control.Monad
base Control.Monad
The Functor, Monad and MonadPlus classes, with some useful operations on monads.
class Monad m => MonadFix m
base Control.Monad.Fix
Monads having fixed points with a 'knot-tying' semantics. Instances of MonadFix should satisfy the following laws: * purity mfix (return . h) = return (fix h) * left shrinking (or tightening) mfix (\x -> a >>= \y -> f x y) = a >>= \y -> mfix (\x -> f x y) * sliding mfix (Control.Monad.liftM h . f) = Control.Monad.liftM h (mfix (f . h)), for strict h. * nesting mfix (\x -> mfix (\y -> f x y)) = mfix (\x -> f x x) This class is used in the translation of the recursive do notation supported by GHC and Hugs.
class Monad m => MonadPlus m
base Control.Monad
Monads that also support choice and failure.
package MonadCatchIO-mtl
Provides a monad-transformer version of the Control.Exception.catch function. For this, it defines the MonadCatchIO class, a subset of MonadIO. It defines proper instances for most monad transformers in the mtl library. Version
package MonadCatchIO-mtl-foreign
Functions like alloca are provided, except not restricted to IO. Version 0.1
package MonadCatchIO-transformers
Provides functions to throw and catch exceptions. Unlike the functions from Control.Exception, which work in IO, these work in any stack of monad transformers (from the transformers package) with IO as the base monad. You can extend this functionality to other monads, by creating an instance of the MonadCatchIO class. Warning: this package is deprecated. Use the exceptions package instead, if possible. Version
package MonadCatchIO-transformers-foreign
Functions like alloca are provided, except not restricted to IO. Version 0.1
class Monad m => MonadIO m
transformers Control.Monad.IO.Class
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: *  . return = *  (m >>= f) = liftIO m >>= > (liftIO .  
package Monadius
A fast-paced 2-D scrolling vector graphics clone of the arcade game Gradius; it is dedicated to the 20th anniversary of Gradius series. Version 0.99
package MonadLab
package MonadPrompt
"Prompting" monad that allows splitting the description of a computation from the implementation of the effects used in that computation. Version
package MonadRandom
Support for computations which consume random values. Version 0.1.12
package MonadRandomLazy
Support for lazy computations which consume random values. Version 0.1
class MonadTrans t
transformers Control.Monad.Trans.Class
The class of monad transformers. Instances should satisfy the following laws, which state that lift is a transformer of monads: *  . return = *  (m >>= f) = lift m >>= > (lift .  
package monad-abort-fd
This package provides automated lifting of operations via functional dependencies for the transformers-abort package. Version 0.4
package monad-atom
package monad-atom-simple
Monadically map objects to unique ints. Version 0.0.2
package monad-bool
This package has been removed. Version 0.2.0
package monad-codec
The library provides functions for encoding and decoding complex data structures with unique integer numbers.  The codec structure can be explicitly defined which distinguishes this package from a monad-atom library. Version 0.2.0

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