[Haskell-beginners] Type classes and synonyms

Philip Scott haskell-beginners at foo.me.uk
Sat Nov 21 16:07:38 EST 2009

> The final piece is that (->) is an Arrow, the most basic one but still
> an Arrow, so if you replace a by (->) in the type of second, you get :
> second :: (->) b c -> (->) (d, b) (d, c)
> which is just
> second :: (b -> c) -> (d, b) -> (d, c)

Ahh I see, very clever! There is method to the madness after all; I should 
never have doubted you Haskell. Thank you for taking the time to explain that 

Do you know of any good discussions/tutorials on Arrows? I've only managed to 
find little snippets here and there


Doesn't have a lot of detail and


..would probably be useful once I actually understand what is going on but 
right now I think a slap in the face with a big wet fish might help me more ;)

- Philip

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