remove localSpanViaKleisli since it's now available in natchez-mtl 0.3.1

Dwolla · Feb 15, 2023 · c32d5d3 · c32d5d3
1 parent 5585044
commit c32d5d3
Showing 1 changed file with 0 additions and 45 deletions.
diff --git a/core/src/main/scala/com/dwolla/tracing/instances/package.scala b/core/src/main/scala/com/dwolla/tracing/instances/package.scala
@@ -1,58 +1,13 @@
 package com.dwolla.tracing
 
 import cats._
-import cats.data._
 import cats.effect.{Trace => _, _}
 import cats.mtl._
-import natchez._
 
 package object instances extends LocalInstances
 
 package instances {
   trait LocalInstances {
-    /** When fulfilling a effect-polymorphic function demanding an implicit
-     * `Local[F, Span[F]]` with `[F[_], A] =>> Kleisli[F, Span[F], A]`,
-     * the implicit instances provided by cats-mtl don't quite fit. The
-     * code demands
-     * `Local[Kleisli[F, Span[F], *], Span[Kleisli[F, Span[F], *]]`,
-     * but `Local.baseLocalForKleisli` returns
-     * `Local[Kleisli[F, Span[F], *], Span[F]]` (the `E` parameter is
-     * wrong), and `Local.localForKleisli` requires an implicit
-     * `Local[F, Span[Kleisli[F, Span[F], *]]`, which we don't have.
-     *
-     * However, it's safe to `imap` the `Local[Kleisli[F, Span[F], *], Span[F]]`
-     * returned by `Local.baseLocalForKleisli` using `Kleisli.liftK` and
-     * `Kleisli.applyK`. `Kleisli.liftK` will turn `Span[F]` into
-     * `Span[Kleisli[F, Span[F], *]]`, which, when run, will ignore any
-     * `Span[F]`s passed to each `Kleisli[F, Span[F], *]`. We take
-     * advantage of that by immediately `mapK`ing it back to `Span[F]`,
-     * applying a no-op span that we know will never actually be used.
-     *
-     * This instance is law-tested in [[https://github.com/tpolecat/natchez/pull/713 tpolecat/natchez#713]],
-     * so it's believed to be a lawful instance.
-     *
-     * TODO Remove when [[https://github.com/tpolecat/natchez/pull/713 tpolecat/natchez#713]] is merged and released
-     *
-     * @param F the `MonadCancel[F, _]` instance demanded by `Span[F].mapK`
-     * @tparam F the effect in which to operate
-     * @return a `Local[Kleisli[F, Span[F], *], Span[Kleisli[F, Span[F], *]]]` instance
-     */
-    implicit def localSpanViaKleisli[F[_]](implicit F: MonadCancel[F, _]): Local[Kleisli[F, Span[F], *], Span[Kleisli[F, Span[F], *]]] =
-      new Local[Kleisli[F, Span[F], *], Span[Kleisli[F, Span[F], *]]] {
-        override def local[A](fa: Kleisli[F, Span[F], A])
-                             (f: Span[Kleisli[F, Span[F], *]] => Span[Kleisli[F, Span[F], *]]): Kleisli[F, Span[F], A] =
-          fa.local {
-            f.andThen(_.mapK(Kleisli.applyK(Span.noop[F])))
-              .compose(_.mapK(Kleisli.liftK))
-          }
-
-        override def applicative: Applicative[Kleisli[F, Span[F], *]] =
-          Kleisli.catsDataApplicativeForKleisli
-
-        override def ask[E2 >: Span[Kleisli[F, Span[F], *]]]: Kleisli[F, Span[F], E2] =
-          Kleisli.ask[F, Span[F]].map(_.mapK(Kleisli.liftK))
-      }
-
     /**
      * Given an `IOLocal[E]`, provides a `Local[IO, E]`.
      *