A sighting of sequence function in Practical FP in Scala

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Slide deck home: http://fpilluminated.com/assets/sighting-of-scala-cats-sequence-function-in-practical-fp-in-scala.html. Download PDF for perfect image quality.

Software

sequence
a sighting of
in
@philip_schwarz
slides by http://fpilluminated.com/
by

with some minor renaming, to ease comprehension
for anyone lacking context – see repo for original

@typeclass trait Traverse[F[_]] extends Functor[F] with Foldable[F] with …
…
Thread all the G effects through the F structure to invert the structure from F[G[A]] to G[F[A]].
def sequence[G[_]: Applicative, A](fga: F[G[A]]): G[F[A]] =
traverse(fga)(ga => ga)
List[F[Unit]] => F[List[Unit]]
case class CartRoutes[F[_]: JsonDecoder: Monad]
Applicative
Monad
Functor
Traverse
Foldable

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