[Haskell-cafe] Where is the documentation on exception types kept?

Albert Y. C. Lai trebla at vex.net
Wed Nov 7 22:08:33 CET 2012

On 12-11-07 03:36 PM, timothyhobbs at seznam.cz wrote:
> I am trying to catch an "thread blocked on MVar indefinitely
> exception."  Of course I can use ::SomeException as explained in
> http://hackage.haskell.org/packages/archive/base/latest/doc/html/Control-Exception.html#g:3
> but there is no explanation as to how to find the more case specific
> exceptions.

In general, because Exception instances are Typeable instances, you can 
get a name, and then you can use that for searches.

import Control.Exception
import Data.Typeable

main = do
   aida <- try (readFile "no")
   case aida of
     Left (SomeException e) -> print (typeOf e)

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