Re: [Haskell-cafe] Problems with type family in a class

On Mon, Jul 21, 2014 at 2:52 PM, Niklas Haas wrote:

You can drop the forall csx. bit, for what it's worth, since csx is an unbound variable either way (and hence implicitly quantified).

Also, the "ComplexSignal csx" constraint is redundant, since the Complexable superclass constraint includes it. In other words, you can write: class (Complexable s) ⇒ FourierTransformable s where fft :: (csx ~ ComplexSignalType s) ⇒ csx → csx