cleff-0.3.4.0: Fast and concise extensible effects

Copyright	(c) 2021 Xy Ren
License	BSD3
Maintainer	xy.r@outlook.com
Stability	experimental
Portability	non-portable (GHC only)
Safe Haskell	Trustworthy
Language	Haskell2010

Cleff.Fail

Contents

Effect
Interpretations
Orphan instances

Description

Synopsis

data Fail :: Effect where
- Fail :: String -> Fail m a
runFail :: Eff (Fail ': es) a -> Eff es (Either String a)
runFailIO :: IOE :> es => Eff (Fail ': es) ~> Eff es

Effect

data Fail :: Effect where Source #

An effect that expresses failure with a message. This effect allows the use of the MonadFail class.

Constructors

Fail :: String -> Fail m a

Interpretations

runFail :: Eff (Fail ': es) a -> Eff es (Either String a) Source #

Run a Fail effect in terms of Error.

runFailIO :: IOE :> es => Eff (Fail ': es) ~> Eff es Source #

Run a Fail effect in terms of throwing exceptions in IO.

Orphan instances

Fail :> es => MonadFail (Eff es) Source #
Instance details Methods fail :: String -> Eff es a #