[Haskell-cafe] Type classes and type equality

[Clifford Beshers]

Jeremy Shaw wrote:
>
> I noticed that the results can be a bit suprising sometimes. See if
> you can predict the answers to these (in ghci):
>   

Interesting examples.  Here's another one that I would find problematic:

    *SameType> same Nothing (Just "xyzzy")
    False
    *SameType> same (Nothing :: Maybe String) (Just "xyzzy")
    True

And of course, the case with the integers lifts right up:

    *SameType> same (Just 1) (Just 1)
    False


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