`show' in ghci dialogue

[Serge D. Mechveliani]

People,

I have a question about usage of `show' in the GHCi dialogue system.

I introduce my user  class DShow,  trying to improve the class Show of
Haskell-98. For example, I program

---------------------------
class DShow a where dShow :: ShowOptions -> a -> String
...
main = let listOfListPairs = [ ([1,2,3], []     ),
                               ([4,5,6], [7]    ),
                               ([9,8,0], [0,0,0])
                             ]                     :: [ ([Int], [Int]) ]
           opts = ShowOptions {verbosity      = 2, 
                               listSepator    = ", \n\n", 
                               fieldSeparator = ", \n"}
       in
       putStr (dShow opts listOfListPairs)
---------------------------

Then, the command  ./Main  outputs 

-----------------------
[([1, 2, 3], []),

([4, 5, 6], [7]),

([9, 8, 0], [0, 0, 0])]
-----------------------

This way of the output format control by dShow and ShowOptions is my goal. 
But the command  

  > main

in the ghci interpreter outputs something like this:

"[([1, 2, 3), []),\n\n([4, 5, 6), [7]),\n\n([9, 8, 0],\n\n[0, 0, 0])]"

How can the user force  ghci  to output the same output format as in 
the case of  ./Main 
(how to interprete '\n') ?

1. If we give to the interpreter the line

   > listOfListPairs

, then the  ghci  dialogue system does interprete the NewLine 
characters on output as needed -- 
only          for the value of  (show listOfListPairs).
And I need it for the value of  (dShow opts listOfListPairs).
Is there any way to substitute a user function instead of `show' in the  
ghci  output?  (and dShow has additional argument ...).

2. Which function  outputs  a string in the  ghci  dialogue system?
   Can the user make this function to interprete the NewLine character 
   in the argument string?

Thank you in advance for your explanation.

-----------------
Serge Mechveliani
mechvel at botik.ru