Hi!

I've been working with GHC-4.6.3, and updating to GHC-4.8.3 breaks my code, 

because the Typeable class has been changed. The compiler produces this 

message:

---------

src/HsShellScript/ProcErr.chs:2294:4:

    ‘typeOf’ is not a (visible) method of class ‘Typeable’

---------

I want to define System.Posix.Process.ProcessStatus to be an instance of 

Typeable, so I can throw and catch it as an exception. ProcessStatus isn't 

typeable by default.

Is it still possible to make ProcessStatus a member of Typeable? How? 

Obviously, you can't accomplish it by deriving Typeable, because the definition 

can't be changed any longer.

This is the spot in question:

----------

import System.Posix.Process

import Data.Typeable

{-

data ProcessStatus = Exited ExitCode

                   | Terminated Signal

                   | Stopped Signal

                   deriving (Eq, Ord, Show)

-}

instance Typeable ProcessStatus where

   typeOf = const tyCon_ProcessStatus

tyCon_ProcessStatus = mkTyConApp (mkTyCon3 "hsshellscript"

                                           "HsShellScript.ProcErr"

                                           "Posix.ProcessStatus") []

instance Exception ProcessStatus

----------

Thanks,

V.W.

_______________________________________________
Glasgow-haskell-users mailing list
Glasgow-haskell-users@haskell.org
http://www.haskell.org/mailman/listinfo/glasgow-haskell-users