[Haskell-beginners] Monad for Pair

Kim-Ee Yeoh ky3 at atamo.com
Thu Nov 19 06:34:48 UTC 2015


On Thu, Nov 19, 2015 at 1:33 AM, Mike Houghton <mike_k_houghton at yahoo.co.uk>
wrote:

The source is just me exploring.
>

Nice.


> I first looked at
>
> data C a = C a deriving (Show)
>
> and made Monad, Applicative, Monoid and Functors for it.
>

Even though the null-effect instances for the identity functor are trivial,
there's value in writing them out, especially for the motivated.

But how do you take an arbitrary type and turn it into a monoid?

-- Kim-Ee
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