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Hi, I am trying to make a Free Monoid of a list using Arrows, but I have some doubts.
When I read about Free, I always see Initial in the context (maybe my reading is biased) I also read [this](<https://kotlinlang.slack.com/archives/C5UPMM0A0/p1554022508033000>), I assume that for to write a Free Monoid I must create two class a "Mempty" and a "Mappend" and I should provide an Interpreter (is this right ?).  But for me, it does not look like [this](<https://github.com/hmemcpy/milewski-ctfp-pdf/blob/master/src/content/2.3/code/scala/snippet02.scala>). Someone can point to me the right direction to do that with using Arrow's (free)[<https://github.com/arrow-kt/arrow/blob/master/modules/free/arrow-free-data/src/main/kotlin/arrow/free/Free.kt>]. Tks for any help and sorry for any trouble;

A Free monoid can be encoded with just a List of terms and the Monoid for their contained item. This is an example in Scala that could be easily ported to Kotlin <https://github.com/typelevel/spire/blob/master/core/src/main/scala/spire/algebra/free/FreeMonoid.scala>

`run` just iterates over the list applying a transformation and combining all internal values with the Monoid of the elements