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vmarquez/SeparateSequence.scala

Last active August 29, 2015 14:11
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SeparateSequence.scala
def sepSeq[A, B, F[_], G[_]](g: G[EitherT[F, A, B]])(implicit F: Monad[F], G: Foldable[G], M: MonadPlus[G]): EitherT[F, A, (G[A],G[B])] =
EitherT(G.foldRight(g, F.point((M.empty[A],M.empty[B])))( (a, l) =>
for {
tup <- l
e <- a.run
} yield
e.fold(le => (M.plus(M.point(le),tup._1), tup._2), re => (tup._1, M.plus(M.point(re), tup._2)))
).map(_.right[A])
)
@vmarquez
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Looks to be a type lambda issue, if I have a type alias the issue goes away.

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