| Safe Haskell | Safe |
|---|---|
| Language | Haskell2010 |
Universum.Exception
Description
Re-exports most useful functionality from 'safe-exceptions'. Also
provides some functions to work with exceptions over MonadError.
- module Control.Exception.Safe
- data Bug = Bug SomeException CallStack
- bug :: (HasCallStack, Exception e) => e -> a
- pattern Exc :: Exception e => e -> SomeException
- note :: MonadError e m => e -> Maybe a -> m a
Documentation
module Control.Exception.Safe
Type that represents exceptions used in cases when a particular codepath is not meant to be ever executed, but happens to be executed anyway.
Constructors
| Bug SomeException CallStack |
bug :: (HasCallStack, Exception e) => e -> a Source #
Generate a pure value which, when forced, will synchronously
throw the exception wrapped into Bug data type.
pattern Exc :: Exception e => e -> SomeException Source #
Pattern synonym to easy pattern matching on exceptions. So intead of writing something like this:
isNonCriticalExc e
| Just (_ :: NodeAttackedError) <- fromException e = True
| Just DialogUnexpected{} <- fromException e = True
| otherwise = False
you can use Exc pattern synonym:
isNonCriticalExc = case
Exc (_ :: NodeAttackedError) -> True -- matching all exceptions of type NodeAttackedError
Exc DialogUnexpected{} -> True
_ -> False
This pattern is bidirectional. You can use Exc e instead of toException e.
note :: MonadError e m => e -> Maybe a -> m a Source #
Throws error for Maybe if Nothing is given.
Operates over MonadError.