data SomeException
class Exception e
data IOException
data ArithException
data ArrayException
data AssertionFailed
data SomeAsyncException
data AsyncException
data NonTermination
data NestedAtomically
data Deadlock
data NoMethodError
data PatternMatchFail
data RecConError
data RecSelError
data RecUpdError
data ErrorCall
catch
functionsdata Handler a
handle
functionstry
functionsevaluate
functionmapException
functiondata MaskingState
mask
to an exception handler