[refined4s-cats] Add contraCoercible to F[B] => F[A] with Contravariant[F] and Coercible[A, B]

[kevin-lee]

Summary

[refined4s-cats] Add contraCoercible to F[B] => F[A] with Contravariant[F] and Coercible[A, B]

Version

0.4.0

Description

This is useful to derive type-class instances for Newtype, Refined and InlinedRefined from the type-class instances of the actual types.

e.g.)

inline given eqDerived[A, B](using coercible: Coercible[A, B], eqB: Eq[B]): Eq[A] =
  contraCoercible(eqB)

inline given showDerived[A, B](using coercible: Coercible[A, B], showB: Show[B]): Show[A] =
  contraCoercible(showB)

where B is the actual type and A could be a newtype or a refined type.