Copyright	(C) 2026 - Eitan Chatav
License	BSD-style (see the file LICENSE)
Maintainer	Eitan Chatav <eitan.chatav@gmail.com>
Stability	provisional
Portability	non-portable
Safe Haskell	None
Language	Haskell2010

Data.Profunctor.Monadic

Contents

Description

This module can provide qualified do-notation for Monadic profunctors.

>>> :set -XQualifiedDo
>>> import qualified Data.Profunctor.Monadic as P

See Control.Lens.Grammar for an example of how to use qualified do-notation with pattern bonding.

Synopsis

type Monadic (p :: Type -> Type -> Type) = (Profunctor p, forall x. Monad (p x))
(>>=) :: Monadic p => p a b -> (b -> p c d) -> p (a, c) (b, d)
(>>) :: Monadic p => p () c -> p a b -> p a b
return :: (Monadic p, Choice p) => Prism a b () () -> p a b
type MonadicTry (p :: Type -> Type -> Type) = (Profunctor p, forall x. MonadTry (p x))
try :: MonadTry m => m a -> m a
fail :: MonadFail m => String -> m a

Monadic

type Monadic (p :: Type -> Type -> Type) = (Profunctor p, forall x. Monad (p x)) Source #

A Profunctor which is also a Monad.

(>>=) :: Monadic p => p a b -> (b -> p c d) -> p (a, c) (b, d) infixl 1 Source #

The pair bonding operator P.>>= is a context-sensitive version of >*<.

x >*< y = x P.>>= (\_ -> y)

(>>) :: Monadic p => p () c -> p a b -> p a b infixl 1 Source #

P.>> sequences actions.

return :: (Monadic p, Choice p) => Prism a b () () -> p a b Source #

P.return is a Monadic-restricted version of pureP.

pureP = P.return

MonadicTry

type MonadicTry (p :: Type -> Type -> Type) = (Profunctor p, forall x. MonadTry (p x)) Source #

A Profunctor which is also a MonadTry.

try :: MonadTry m => m a -> m a Source #

A handler for failures. Used for backtracking state on failure in Parsector.