[Haskell-cafe] Flexible instances
bulat.ziganshin at gmail.com
Wed Oct 15 06:30:23 EDT 2008
Wednesday, October 15, 2008, 7:51:06 AM, you wrote:
>>> Illegal instance declaration for `Stringable [Char]'
>>> (All instance types must be of the form (T a1 ... an)
>>> where a1 ... an are distinct type *variables*
> Just in case: n=0 for "instance Eq Blah", i.e., "T a1 ... an" becomes "T".
and [Char] =  Char, where Char isn't type variable but constant
Bulat mailto:Bulat.Ziganshin at gmail.com
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