
Data.Either.Utils  Portability  portable  Stability  provisional  Maintainer  John Goerzen <jgoerzen@complete.org> 



Description 
Utilities for working with the Either data type
Copyright (c) 2004 John Goerzen, jgoerzen@complete.org


Synopsis 



Documentation 

maybeToEither 
:: MonadError e m   => e  (Left e) will be returned if the Maybe value is Nothing
 > Maybe a  (Right a) will be returned if this is (Just a)
 > m a   Converts a Maybe value to an Either value, using the supplied parameter
as the Left value if the Maybe is Nothing.
This function can be interpreted as:
maybeToEither :: e > Maybe a > Either e a Its definition is given as it is so that it can be used in the Error and related monads.



forceEither :: Show e => Either e a > a 
Pulls a Right value out of an Either value. If the Either value is
Left, raises an exception with error.


forceEitherMsg :: Show e => String > Either e a > a 
Like forceEither, but can raise a specific message with the error.


eitherToMonadError :: MonadError e m => Either e a > m a 
Takes an either and transforms it into something of the more generic
MonadError class.


Produced by Haddock version 0.8 