Re: [Haskell-fr] Fw: Éclaircissements sur les monades

On 05/24/2014 08:49 PM, Gautier DI FOLCO wrote:

J'ai tenté ça : runState (pure (-) <*> pure 4 <*> pure 2) 7

State f `ap1` State g = State $ \x -> let (a, b) = g x in let (c, d) = f b in (c a, d) State f `ap2` State g = State $ \x -> let (c, d) = f x in let (a, b) = g d in (c a, b) *Xxxx> runState (pure (,) `ap2` put 4 `ap2` put 7) 0 (((),()),7) *Xxxx> runState (pure (,) `ap1` put 4 `ap1` put 7) 0 (((),()),4)