Deprecate and make private syntax methods that are now on Either (#3149)

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

@@ -37,12 +37,14 @@ object EitherSyntax {
 }
 
 final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
- def foreach(f: B => Unit): Unit = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def foreach(f: B => Unit): Unit = eab match {
  case Left(_) => ()
  case Right(b) => f(b)
  }
 
- def getOrElse[BB >: B](default: => BB): BB = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def getOrElse[BB >: B](default: => BB): BB = eab match {
  case Left(_) => default
  case Right(b) => b
  }
@@ -67,12 +69,14 @@ final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
  case Right(b) => b
  }
 
- def forall(f: B => Boolean): Boolean = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def forall(f: B => Boolean): Boolean = eab match {
  case Left(_) => true
  case Right(b) => f(b)
  }
 
- def exists(f: B => Boolean): Boolean = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def exists(f: B => Boolean): Boolean = eab match {
  case Left(_) => false
  case Right(b) => f(b)
  }
@@ -89,7 +93,8 @@ final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
 
  def toIor: A Ior B = Ior.fromEither(eab)
 
- def toOption: Option[B] = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def toOption: Option[B] = eab match {
  case Left(_) => None
  case Right(b) => Some(b)
  }
@@ -99,7 +104,8 @@ final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
  case Right(b) => List(b)
  }
 
- def toTry(implicit ev: A <:< Throwable): Try[B] = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def toTry(implicit ev: A <:< Throwable): Try[B] = eab match {
  case Left(a) => Failure(ev(a))
  case Right(b) => Success(b)
  }
@@ -129,23 +135,25 @@ final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
  case Right(b) => Right(fb(b))
  }
 
- def map[C](f: B => C): Either[A, C] = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def map[C](f: B => C): Either[A, C] = eab match {
  case l @ Left(_) => EitherUtil.rightCast(l)
  case Right(b) => Right(f(b))
  }
 
  def map2Eval[AA >: A, C, Z](fc: Eval[Either[AA, C]])(f: (B, C) => Z): Eval[Either[AA, Z]] =
  eab match {
  case l @ Left(_) => Now(EitherUtil.rightCast(l))
- case Right(b) => fc.map(either => new EitherOps(either).map(f(b, _)))
+ case Right(b) => fc.map(_.map(f(b, _)))
  }
 
  def leftMap[C](f: A => C): Either[C, B] = eab match {
  case Left(a) => Left(f(a))
  case r @ Right(_) => EitherUtil.leftCast(r)
  }
 
- def flatMap[AA >: A, D](f: B => Either[AA, D]): Either[AA, D] = eab match {
+ @deprecated("Included in the standard library", "2.1.0-RC1")
+ private[syntax] def flatMap[AA >: A, D](f: B => Either[AA, D]): Either[AA, D] = eab match {
  case l @ Left(_) => EitherUtil.rightCast(l)
  case Right(b) => f(b)
  }
@@ -256,7 +264,7 @@ final class EitherOps[A, B](private val eab: Either[A, B]) extends AnyVal {
  case Right(b) => s"Right(${BB.show(b)})"
  }
 
- def ap[AA >: A, BB >: B, C](that: Either[AA, BB => C]): Either[AA, C] = new EitherOps(that).flatMap(this.map)
+ def ap[AA >: A, BB >: B, C](that: Either[AA, BB => C]): Either[AA, C] = that.flatMap(eab.map)
 
  /**
  * Transform the `Either` into a [[cats.data.EitherT]] while lifting it into the specified Applicative.