Merge pull request #460 from Dwolla/kleisli

add instance for Logger[Kleisli[F, A, *]]
typelevel · Jun 26, 2021 · 8440a1f · 8440a1f
2 parents 53b77ec + 56b4b6b
commit 8440a1f
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Showing 2 changed files with 14 additions and 1 deletion.
diff --git a/core/shared/src/main/scala/org/typelevel/log4cats/Logger.scala b/core/shared/src/main/scala/org/typelevel/log4cats/Logger.scala
@@ -17,7 +17,7 @@
 package org.typelevel.log4cats
 
 import cats._
-import cats.data.{EitherT, OptionT}
+import cats.data.{EitherT, Kleisli, OptionT}
 
 trait Logger[F[_]] extends MessageLogger[F] with ErrorLogger[F] {
   def withModifiedString(f: String => String): Logger[F] = Logger.withModifiedString[F](this, f)
@@ -33,6 +33,9 @@ object Logger {
   implicit def eitherTLogger[F[_]: Logger: Functor, E]: Logger[EitherT[F, E, *]] =
     Logger[F].mapK(EitherT.liftK[F, E])
 
+  implicit def kleisliLogger[F[_]: Logger, A]: Logger[Kleisli[F, A, *]] =
+    Logger[F].mapK(Kleisli.liftK[F, A])
+
   private def withModifiedString[F[_]](l: Logger[F], f: String => String): Logger[F] =
     new Logger[F] {
       def error(message: => String): F[Unit] = l.error(f(message))

diff --git a/.../shared/src/test/scala/org/typelevel/log4cats/extras/syntax/LoggerSyntaxCompilation.scala b/.../shared/src/test/scala/org/typelevel/log4cats/extras/syntax/LoggerSyntaxCompilation.scala
@@ -17,6 +17,7 @@
 package org.typelevel.log4cats.extras.syntax
 
 import cats._
+import cats.data.{EitherT, Kleisli, OptionT}
 import org.typelevel.log4cats._
 
 object LoggerSyntaxCompilation {
@@ -52,4 +53,13 @@ object LoggerSyntaxCompilation {
   ): SelfAwareStructuredLogger[F] =
     l.withModifiedString(identity)
 
+  def eitherTLogger[F[_]: Functor: Logger, A]: EitherT[F, A, Unit] =
+    Logger[EitherT[F, A, *]].info("foo")
+
+  def kleisliLogger[F[_]: Logger, A]: Kleisli[F, A, Unit] =
+    Logger[Kleisli[F, A, *]].info("bar")
+
+  def optionTLogger[F[_]: Functor: Logger]: OptionT[F, Unit] =
+    Logger[OptionT[F, *]].info("baz")
+
 }