Kind projector function syntax

compose.scala

// underlying: Ref[F, A]
// trans: F ~> G
// underlying.access: F[(A, A => F[Boolean])]

// Mapping from F[(A, A => F[Boolean])] to G[(A, A => G[Boolean])]
override def access: G[(A, A => G[Boolean])] =
  trans(F.compose[(A, ?)].compose[A => ?].map(underlying.access)(trans(_)))


// Step by Step
// Functor[F[_]] // compose[(A, ?)] 
// -> Functor[F[(A, _)]] // compose[A => ?] 
// -> Functor[F[(A, A => _)]]