[Haskell-cafe] Type family problem

Sjoerd Visscher sjoerd at w3future.com
Tue Jan 20 17:33:34 EST 2009


Hi all,

When I try this bit of code:

 > class C1 a where
 >   type F a :: *
 >   x :: F a
 >   y :: F a
 >   x = y

I get this error:

     Couldn't match expected type `F a1' against inferred type `F a'
     In the expression: y
     In the definition of `x': x = y

I can't figure out what is going on or how I should fix this.

--
Sjoerd Visscher
sjoerd at w3future.com





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