in coreJVM

core/src/main/scala-2/src/main/scala/cats/compat/targetName.scala

@@ -21,8 +21,9 @@
 
 package cats.compat
 
+import cats.kernel.compat.unused
+
 import scala.annotation.Annotation
-import scala.annotation.nowarn
 
 // compat dummy so we can use targetName on scala 3 to get out of bincompat pickles
-private[cats] class targetName(@nowarn("cat=unused-params") dummy: String) extends Annotation
+private[cats] class targetName(@unused dummy: String) extends Annotation

core/src/main/scala/cats/ApplicativeError.scala

@@ -24,8 +24,8 @@ package cats
 import cats.ApplicativeError.CatchOnlyPartiallyApplied
 import cats.data.{EitherT, Validated}
 import cats.data.Validated.{Invalid, Valid}
+import cats.kernel.compat.unused
 
-import scala.annotation.nowarn
 import scala.reflect.ClassTag
 import scala.util.control.NonFatal
 import scala.util.{Failure, Success, Try}
@@ -355,12 +355,7 @@ object ApplicativeError {
   final private[cats] class CatchOnlyPartiallyApplied[T, F[_], E](private val F: ApplicativeError[F, E])
       extends AnyVal {
 
-    def apply[A](f: => A)(implicit
-      CT: ClassTag[T],
-      @nowarn("cat=unused-params")
-      NT: NotNull[T],
-      ev: Throwable <:< E
-    ): F[A] =
+    def apply[A](f: => A)(implicit CT: ClassTag[T], @unused NT: NotNull[T], ev: Throwable <:< E): F[A] =
       try {
         F.pure(f)
       } catch {

core/src/main/scala/cats/data/Const.scala

@@ -23,7 +23,7 @@ package cats
 package data
 
 import cats.kernel.{CommutativeMonoid, CommutativeSemigroup, LowerBounded, UpperBounded}
-import scala.annotation.nowarn
+import cats.kernel.compat.unused
 
 /**
  * [[Const]] is a phantom type, it does not contain a value of its second type parameter `B`
@@ -40,7 +40,7 @@ final case class Const[A, B](getConst: A) {
   def combine(that: Const[A, B])(implicit A: Semigroup[A]): Const[A, B] =
     Const(A.combine(getConst, that.getConst))
 
-  def traverse[F[_], C](@nowarn("cat=unused-params") f: B => F[C])(implicit F: Applicative[F]): F[Const[A, C]] =
+  def traverse[F[_], C](@unused f: B => F[C])(implicit F: Applicative[F]): F[Const[A, C]] =
     F.pure(retag[C])
 
   def ===(that: Const[A, B])(implicit A: Eq[A]): Boolean =

core/src/main/scala/cats/data/IndexedReaderWriterStateT.scala

@@ -558,7 +558,7 @@ abstract private[data] class RWSFunctions {
   def apply[E, L, S, A](f: (E, S) => (L, S, A)): ReaderWriterState[E, L, S, A] =
     ReaderWriterStateT.applyF(Now((e, s) => Now(f(e, s))))
 
-  @deprecated("2.8.0", "Use apply without the Monoid constraint")
+  @deprecated("Use apply without the Monoid constraint", "2.8.0")
   protected def apply[E, L: Monoid, S, A](f: (E, S) => (L, S, A)): ReaderWriterState[E, L, S, A] =
     ReaderWriterStateT.applyF(Now((e, s) => Now(f(e, s))))
 

core/src/main/scala/cats/data/Validated.scala

@@ -24,8 +24,8 @@ package data
 
 import cats.data.Validated.{Invalid, Valid}
 import cats.kernel.CommutativeSemigroup
+import cats.kernel.compat.unused
 
-import scala.annotation.nowarn
 import scala.reflect.ClassTag
 import scala.util.{Failure, Success, Try}
 
@@ -869,11 +869,7 @@ object Validated extends ValidatedInstances with ValidatedFunctions with Validat
   final private[data] class CatchOnlyPartiallyApplied[T](private val dummy: Boolean = true) extends AnyVal {
     /* Note: the NT parameter is not referenced at runtime, but serves a compile-time role.
      * See https://github.com/typelevel/cats/pull/1867/files#r138381991 for details. */
-    def apply[A](f: => A)(implicit
-      T: ClassTag[T],
-      @nowarn("cat=unused-params")
-      NT: NotNull[T]
-    ): Validated[T, A] =
+    def apply[A](f: => A)(implicit T: ClassTag[T], @unused NT: NotNull[T]): Validated[T, A] =
       try {
         valid(f)
       } catch {

core/src/main/scala/cats/syntax/applicativeError.scala

@@ -23,8 +23,8 @@ package cats
 package syntax
 
 import cats.data.{EitherT, Validated}
+import cats.kernel.compat.unused
 
-import scala.annotation.nowarn
 import scala.reflect.ClassTag
 
 trait ApplicativeErrorSyntax {
@@ -33,8 +33,7 @@ trait ApplicativeErrorSyntax {
 
   implicit final def catsSyntaxApplicativeError[F[_], E, A](fa: F[A])(implicit
     // Although not used directly but helps the compiler to deduce type `E`.
-    @nowarn("cat=unused-params")
-    F: ApplicativeError[F, E]
+    @unused F: ApplicativeError[F, E]
   ): ApplicativeErrorOps[F, E, A] =
     new ApplicativeErrorOps[F, E, A](fa)
 }

core/src/main/scala/cats/syntax/either.scala

@@ -23,8 +23,8 @@ package cats
 package syntax
 
 import cats.data._
+import cats.kernel.compat.unused
 
-import scala.annotation.nowarn
 import scala.reflect.ClassTag
 import scala.util.{Failure, Success, Try}
 import EitherSyntax._
@@ -48,11 +48,7 @@ object EitherSyntax {
    * Uses the [[http://typelevel.org/cats/guidelines.html#partially-applied-type-params Partially Applied Type Params technique]] for ergonomics.
    */
   final private[syntax] class CatchOnlyPartiallyApplied[T](private val dummy: Boolean = true) extends AnyVal {
-    def apply[A](f: => A)(implicit
-      CT: ClassTag[T],
-      @nowarn("cat=unused-params")
-      NT: NotNull[T]
-    ): Either[T, A] =
+    def apply[A](f: => A)(implicit CT: ClassTag[T], @unused NT: NotNull[T]): Either[T, A] =
       try {
         Right(f)
       } catch {
@@ -371,7 +367,7 @@ final class EitherObjectOps(private val either: Either.type) extends AnyVal with
 
   def leftNes[A, B](a: A)(implicit O: Order[A]): EitherNes[A, B] = Left(NonEmptySet.one(a))
 
-  @deprecated("2.8.0", "Use rightNes without Order constraint")
+  @deprecated("Use rightNes without Order constraint", "2.8.0")
   protected def rightNes[A, B](b: B)(implicit O: Order[B]): EitherNes[A, B] = Right(b)
 
   def leftNel[A, B](a: A): EitherNel[A, B] = Left(NonEmptyList.one(a))