failure-0.2.0.3: A simple type class for success/failure computations. (deprecated)

Safe HaskellSafe
LanguageHaskell98

Control.Failure

Contents

Description

Type classes for returning failures.

Note: This module used to contain a lot more functionality, but I believe it was unused functionality. If you want any of it back, just email me.

Synopsis

Type class

class Monad f => Failure e f where Source

Methods

failure :: e -> f v Source

Instances

Exception e => Failure e IO Source 
Failure e [] Source 
Failure e Maybe Source 
(MonadTrans t, Failure e m, Monad (t m)) => Failure e (t m) Source

Instance for all monad transformers, simply lift the failure into the base monad.

Failure e (Either e) Source 

General exceptions

exception :: (Exception e, Failure SomeException m) => e -> m a Source

Convert to a SomeException via toException before calling failure.