[Haskell-cafe] Flexible instances

Bulat Ziganshin bulat.ziganshin at gmail.com
Wed Oct 15 06:30:23 EDT 2008


Hello Albert,

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


-- 
Best regards,
 Bulat                            mailto:Bulat.Ziganshin at gmail.com



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