Simon & I have discussed some changes to various names in GHC's exception
support, details below, comments appreciated.
Problems:
* IOErrors are currently distinct from Exceptions. You can't catch
an exception with IO.catch or throw one with IO.ioError.
* the most commonly used exception catching function, namely
catchAllIO, has the longest name.
* raiseInThread is a horrible name.
Proposal:
* type IOError = Exception.
* Rename the current IOError type to IOException, and make the
appropriate change to the Exception data type.
* New catch family (in module Exception):
catch :: IO a -> (Exception -> IO a) -> IO a
catchJust :: (Exception -> Maybe b) -> IO a -> (b -> IO a) -> IO a
evaluate :: a -> IO a
evaluate a = a `seq` return a
ioExceptions :: Exception -> Maybe IOError
arithExceptions :: Exception -> Maybe ArithException
etc.
(and similarly for the 'try' family).
so eg.
catchAll expr (\ex -> ...)
is now
catch (evaluate expr) (\err -> ...)
* Rename raiseInThread to throwTo.
Cheers,
SImon
