Re: [Haskell-beginners] Sum a tuple of Monoids

I don't know if there is generally, but some people would use the lens library to do such things. import Control.Lens

sumOf (each . _Just) (Just 1, Nothing, Just 2) 3

Just keep in mind that each member of the tuple must be the same type. On Tue, Nov 1, 2016 at 11:42 AM, Lai Boon Hui wrote:

Hi all,

Is it possible to sum a tuple of monoids for example

sum (Just 1, Nothing)

expected result Just 1

sum (Just 1, Just 2)

expected result Just 3

-- Best Regards, Boon Hui

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