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Equal[Option[A]] ambiguity with Cats 2.2.0
Scastie. With Shims 2.2.0 and Cats 2.2.0, we get this:
import scalaz.Scalaz._
import shims.eqToScalaz
implicitly[scalaz.Equal[Option[Short]]]
//ambiguous implicit values:
// both method optionOrder in trait OptionInstances of type [A](implicit A0: scalaz.Order[A])scalaz.Order[Option[A]]
// and method eqToScalaz in trait EqConversions of type [A](implicit AC: shims.util.Capture[cats.kernel.Eq[A]])scalaz.Equal[A] with shims.conversions.Synthetic
// match expected type scalaz.Equal[Option[Short]]
//could not find implicit value for parameter e: scalaz.Equal[Option[Short]]
//not enough arguments for method implicitly: (implicit e: scalaz.Equal[Option[Short]])scalaz.Equal[Option[Short]].
//Unspecified value parameter e.
Looks like there are a lot of other compatibility issues with Cats 2.2.0 - see the test failure in the scala-steward PR.