Re: [Haskell-cafe] Type synonyms considered harmful?

Now we're definitely getting somewhere! I'm not to thrilled about the use of string literals though. How about this? {-# LANGUAGE TypeOperators, DataKinds, RankNTypes #-} type (l ∷ t) = t foo :: forall red green blue. (red ∷ Double) -> (green ∷ Double) -> (blue ∷ Double) -> IO () We just need to patch hlint to make this the suggested style. - jeremy On Sun, Jan 18, 2015 at 7:05 PM, Niklas Haas wrote:

On Mon, 19 Jan 2015 01:12:58 +0100, Christopher Done wrote:

...

...

foo : (x : Int) -> (y : Int) -> (red : Double) -> (blue : Double) -> (green : Double) -> IO ()

And that will solve everything! What could possibly go wrong!

How about a type-level the? =p

type The label t = t

foo :: The red Double -> The green Double -> The blue Double -> IO ()

Or with polykinds:

foo :: The "Red" Double -> The "Green" Double -> The "Blue" Double -> IO ()

Clearly needs more TypeOperators.

type (l ∷ t) = t

foo :: ("red" ∷ Double) -> ("green" ∷ Double) -> ("blue" ∷ Double) -> IO () _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe