I wonder if pattern matching could be less verbose. Maybe this sounds weird, but here is example of what I mean:
> type A = (Int, String) > > f :: String -> A -> A > f s (i,s') = (i, s ++ s') > > data B = B Int String deriving Show > >g :: String -> B -> B >g s (B i s') = B i $ s ++ s' Types A/B and functions f/g are quite similar: (x :: A) or (x :: B) means that x contains some integer and string values, and f/g functions take some string and prepend it to the string part of x. The code for f and g has the same level of verbosity, but -- ta-dah! -- we can use arrows and define f in a highly laconic manner: > import Control.Arrow > f' :: String -> A -> A > f' = second . (++) So my queastion is how I could define (g' :: String -> B -> B) in the same way.
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