Portability | non-portable |
---|---|
Stability | experimental |
Maintainer | Edward Kmett <ekmett@gmail.com> |
Safe Haskell | Trustworthy |
- class Handleable e m h | h -> e m where
- data HandlingException = HandlingException
Documentation
class Handleable e m h | h -> e m whereSource
Both MonadCatchIO-transformers
and Control.Exception provide a Handler
type.
This lets us write combinators to build handlers that are agnostic about the choice of which of these they use.
handler :: Getting (First a) e t a b -> (a -> m r) -> h rSource
This builds a Handler
for just the targets of a given Prism
(or any Getter
, really)
catches
... [handler
_AssertionFailed
(s -> print $ "Assertion Failed\n" ++ s) ,handler
_ErrorCall
(s -> print $ "Error\n" ++ s) ]
This works ith both the Handler
type provided by Control.Exception
:
handler
::Getter
SomeException
a -> (a ->IO
r) ->Handler
rhandler
::Fold
SomeException
a -> (a ->IO
r) ->Handler
rhandler
::Prism'
SomeException
a -> (a ->IO
r) ->Handler
rhandler
::Lens'
SomeException
a -> (a ->IO
r) ->Handler
rhandler
::Traversal'
SomeException
a -> (a ->IO
r) ->Handler
r
and with the Handler
type provided by Control.Monad.CatchIO
:
handler
::Getter
SomeException
a -> (a -> m r) ->Handler
m rhandler
::Fold
SomeException
a -> (a -> m r) ->Handler
m rhandler
::Prism'
SomeException
a -> (a -> m r) ->Handler
m rhandler
::Lens'
SomeException
a -> (a -> m r) ->Handler
m rhandler
::Traversal'
SomeException
a -> (a -> m r) ->Handler
m r
and with the Handler
type provided by Control.Monad.Error.Lens
:
handler
::Getter
e a -> (a -> m r) ->Handler
e m rhandler
::Fold
e a -> (a -> m r) ->Handler
e m rhandler
::Prism'
e a -> (a -> m r) ->Handler
e m rhandler
::Lens'
e a -> (a -> m r) ->Handler
e m rhandler
::Traversal'
e a -> (a -> m r) ->Handler
e m r
handler_ :: Getting (First a) e t a b -> m r -> h rSource
This builds a Handler
for just the targets of a given Prism
(or any Getter
, really)
that ignores its input and just recovers with the stated monadic action.
catches
... [handler_
_NonTermination
(return
"looped") ,handler_
_StackOverflow
(return
"overflow") ]
This works with the Handler
type provided by Control.Exception
:
handler_
::Getter
SomeException
a ->IO
r ->Handler
rhandler_
::Fold
SomeException
a ->IO
r ->Handler
rhandler_
::Prism'
SomeException
a ->IO
r ->Handler
rhandler_
::Lens'
SomeException
a ->IO
r ->Handler
rhandler_
::Traversal'
SomeException
a ->IO
r ->Handler
r
and with the Handler
type provided by Control.Monad.CatchIO
:
handler_
::Getter
SomeException
a -> m r ->Handler
m rhandler_
::Fold
SomeException
a -> m r ->Handler
m rhandler_
::Prism'
SomeException
a -> m r ->Handler
m rhandler_
::Lens'
SomeException
a -> m r ->Handler
m rhandler_
::Traversal'
SomeException
a -> m r ->Handler
m r
and with the Handler
type provided by Control.Monad.Error.Lens
:
handler_
::Getter
e a -> m r ->Handler
e m rhandler_
::Fold
e a -> m r ->Handler
e m rhandler_
::Prism'
e a -> m r ->Handler
e m rhandler_
::Lens'
e a -> m r ->Handler
e m rhandler_
::Traversal'
e a -> m r ->Handler
e m r
Handleable SomeException IO Handler | |
Handleable SomeException m (Handler m) | |
Handleable e m (Handler e m) |
data HandlingException Source
There was exception caused by abusing the internals of a Handler
.