[Haskell-cafe] Re: Generic types

Cale Gibbard cgibbard at gmail.com
Tue Jun 14 04:15:12 EDT 2005

For extra fun, notice that you can make declarations like:

data (Unit u) => Kilo u = Kilo u

instance (Unit u) => Unit (Kilo u) where
    shortName (Kilo u) = "k" ++ shortName u

which behaves in ghci like:
*Main> UnitValue (Kilo Meter) 30

 - Cale

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