[Haskell-cafe] Typeclasses and instances

Mark Carroll mark at ixod.org
Thu Mar 17 14:57:47 EST 2005

Another note, with more help from friends:

It turns out that GHC 6.4 will let me do,

	newtype Floating a => Test a = Test [a] deriving Show

	x = Test [False, True]

but, if I change "newtype" to "data", it then says,

	No instance for (Floating Bool)

I'm not sure I quite understand what's going on.

-- Mark

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