gistfile1.sh

[work06]$ vim mffp.hs 
[work06]$ ghci
GHCi, version 7.6.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Prelude> :l mffp.hs
[1 of 1] Compiling Main             ( mffp.hs, interpreted )
Ok, modules loaded: Main.
*Main> :t answer
answer :: Term
*Main> :t err
err :: Term
*Main> eval answer
42
*Main> eval err
*** Exception: divide by zero
*Main> eval1 answer
Return 42
*Main> eval1 err
Raise "divide by zero (eval1)"
*Main> eval2 answer
Return 42
*Main> eval2 err
Return *** Exception: divide by zero
*Main> eval2' answer
Return 42
*Main> eval2' err
Raise "divide by zero (eval2')"
*Main>