[Haskell] Better Exception Handling

[John Goerzen]

On Wed, Nov 24, 2004 at 06:12:27PM +0000, Jules Bean wrote:
> Ok, I glanced through your code, and you seem to be reimplementing many  
> of the ideas in the MonadError class, which also makes Either into a  
> Monad.
> 
> http://www.haskell.org/ghc/docs/latest/html/libraries/base/ 
> Control.Monad.Error.html

That documentation is really poor.  I really have no idea what problem
this module solves, why I should use it, or how I should use it from the
documentation presented.  

It would be great if someone clarified that a bit.

I note, though, that "making an Either into a Monad" doesn't do anything
to deal with asynchronous exceptions.

-- John