Re: [Haskell-beginners] Exercise of "Programming with Arrows"

On Wed, Oct 16, 2013 at 10:33 PM, Thiago Negri wrote:

Updated gist: https://gist.github.com/thiago-negri/2e541a9f9762c727bdd4

Here: prop_SP_first :: SP Int Int -> [(Int,Int)] -> Bool prop_SP_first f xs = x1 == x2 where x1 = map snd xs x2 = map snd (runSP (first f) xs) you check that the second half of the coupled stream are equal, i.e. the (arr id) input of (***) is equivalent across the equal sign: g *** (arr id) = first g What about the first half? -- Kim-Ee