Show and Integral

Serge D. Mechveliani mechvel at
Fri Dec 23 18:53:42 CET 2011

Sorry, I have forgotten to copy to the List my last note on this subject.

The on-line spec of Haskell-2010 shows

                  Eq     Show
                    \   /

Hence, for   x :: Integral a => a,   it is correct to apply  (show x).
And  ghc-  does not allow this  (show x).
So, it breaks the standard, and people say, this is deliberate.
I witness such a break for the first time, and this looks so strange!
Well, I also diskile the edge  Show 
in the standard. But it is better to implement Show as dummy for appropriate
types, -- so far, -- and to wait for the next standard.
Am I missing something?


mechvel at

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