Add Syntax For Enumerable

Also load the existing definitions PartialNext/PartialPrevious into implicit scope.

Author: isomarcte

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

@@ -32,6 +32,7 @@ abstract class AllSyntaxBinCompat
     with AllSyntaxBinCompat5
     with AllSyntaxBinCompat6
     with AllSyntaxBinCompat7
+    with AllSyntaxBinCompat8
 
 trait AllSyntax
     extends AlternativeSyntax
@@ -122,3 +123,10 @@ trait AllSyntaxBinCompat5 extends ParallelBitraverseSyntax
 trait AllSyntaxBinCompat6 extends ParallelUnorderedTraverseSyntax
 
 trait AllSyntaxBinCompat7 extends SeqSyntax
+
+trait AllSyntaxBinCompat8
+    extends PartialNextSyntax
+    with NextSyntax
+    with PartialPreviousSyntax
+    with PreviousSyntax
+    with BoundedEnumerableSyntax

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

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2015 Typelevel
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+package cats
+package syntax
+
+import cats.kernel._
+
+trait PartialNextSyntax {
+  implicit final def catsSyntaxPartialNext[A](a: A): PartialNextOps[A] =
+    new PartialNextOps(a)
+}
+
+final class PartialNextOps[A](private val lhs: A) extends AnyVal {
+  def partialNext(implicit A: PartialNext[A]): Option[A] =
+    A.partialNext(lhs)
+}
+
+trait NextSyntax extends PartialNextSyntax {
+  implicit final def catsSyntaxNext[A](a: A): NextOps[A] =
+    new NextOps(a)
+}
+
+final class NextOps[A](private val lhs: A) extends AnyVal {
+  def next(implicit A: Next[A]): A =
+    A.next(lhs)
+}
+
+trait PartialPreviousSyntax {
+  implicit final def catsSyntaxPartialPrevious[A](a: A): PartialPreviousOps[A] =
+    new PartialPreviousOps(a)
+}
+
+final class PartialPreviousOps[A](private val lhs: A) extends AnyVal {
+  def partialPrevious(implicit A: PartialPrevious[A]): Option[A] =
+    A.partialPrevious(lhs)
+}
+
+trait PreviousSyntax extends PartialPreviousSyntax {
+  implicit final def catsSyntaxPrevious[A](a: A): PreviousOps[A] =
+    new PreviousOps(a)
+}
+
+final class PreviousOps[A](private val lhs: A) extends AnyVal {
+  def previous(implicit A: Previous[A]): A =
+    A.previous(lhs)
+}
+
+trait BoundedEnumerableSyntax extends NextSyntax with PreviousSyntax {
+  implicit final def catsSyntaxForBoundedEnumerable[A](a: A): BoundedEnumerableOps[A] =
+    new BoundedEnumerableOps(a)
+}
+
+final class BoundedEnumerableOps[A](private val lhs: A) extends AnyVal {
+  def cycleNext(implicit A0: PartialNext[A], A1: LowerBounded[A]): A =
+    A0.partialNext(lhs).getOrElse(A1.minBound)
+
+  def cyclePrevious(implicit A0: PartialPrevious[A], A1: UpperBounded[A]): A =
+    A0.partialPrevious(lhs).getOrElse(A1.maxBound)
+}

kernel/src/main/scala/cats/kernel/Enumerable.scala

@@ -33,6 +33,29 @@ trait PartialNext[@sp A] {
   def partialNext(a: A): Option[A]
 }
 
+object PartialNext {
+
+  def apply[A](implicit A: PartialNext[A]): PartialNext[A] =
+    A
+
+  implicit def catsKernelPartialNextForUnit: PartialNext[Unit] =
+    cats.kernel.instances.unit.catsKernelStdOrderForUnit
+  implicit def catsKernelPartialNextForBoolean: PartialNext[Boolean] =
+    cats.kernel.instances.boolean.catsKernelStdOrderForBoolean
+  implicit def catsKernelPartialNextForByte: PartialNext[Byte] =
+    cats.kernel.instances.byte.catsKernelStdOrderForByte
+  implicit def catsKernelPartialNextForInt: PartialNext[Int] =
+    cats.kernel.instances.int.catsKernelStdOrderForInt
+  implicit def catsKernelPartialNextForShort: PartialNext[Short] =
+    cats.kernel.instances.short.catsKernelStdOrderForShort
+  implicit def catsKernelPartialNextForLong: PartialNext[Long] =
+    cats.kernel.instances.long.catsKernelStdOrderForLong
+  implicit def catsKernelPartialNextForChar: PartialNext[Char] =
+    cats.kernel.instances.char.catsKernelStdOrderForChar
+  implicit def catsKernelPartialNextForBigInt: PartialNext[BigInt] =
+    cats.kernel.instances.bigInt.catsKernelStdOrderForBigInt
+}
+
 /**
  * A typeclass with an operation which returns a member which is
  * always greater than the one supplied.
@@ -42,6 +65,14 @@ trait Next[@sp A] extends PartialNext[A] {
   override def partialNext(a: A): Option[A] = Some(next(a))
 }
 
+object Next {
+  def apply[A](implicit A: Next[A]): Next[A] =
+    A
+
+  implicit def catsKernelNextForBigInt: Next[BigInt] =
+    cats.kernel.instances.bigInt.catsKernelStdOrderForBigInt
+}
+
 /**
  * A typeclass with an operation which returns a member which is
  * smaller or `None` than the one supplied.
@@ -51,6 +82,28 @@ trait PartialPrevious[@sp A] {
   def partialPrevious(a: A): Option[A]
 }
 
+object PartialPrevious {
+  def apply[A](implicit A: PartialPrevious[A]): PartialPrevious[A] =
+    A
+
+  implicit def catsKernelPartialPreviousForUnit: PartialPrevious[Unit] =
+    cats.kernel.instances.unit.catsKernelStdOrderForUnit
+  implicit def catsKernelPartialPreviousForBoolean: PartialPrevious[Boolean] =
+    cats.kernel.instances.boolean.catsKernelStdOrderForBoolean
+  implicit def catsKernelPartialPreviousForByte: PartialPrevious[Byte] =
+    cats.kernel.instances.byte.catsKernelStdOrderForByte
+  implicit def catsKernelPartialPreviousForInt: PartialPrevious[Int] =
+    cats.kernel.instances.int.catsKernelStdOrderForInt
+  implicit def catsKernelPartialPreviousForShort: PartialPrevious[Short] =
+    cats.kernel.instances.short.catsKernelStdOrderForShort
+  implicit def catsKernelPartialPreviousForLong: PartialPrevious[Long] =
+    cats.kernel.instances.long.catsKernelStdOrderForLong
+  implicit def catsKernelPartialPreviousForChar: PartialPrevious[Char] =
+    cats.kernel.instances.char.catsKernelStdOrderForChar
+  implicit def catsKernelPartialPreviousForBigInt: PartialPrevious[BigInt] =
+    cats.kernel.instances.bigInt.catsKernelStdOrderForBigInt
+}
+
 /**
  * A typeclass with an operation which returns a member which is
  * always smaller than the one supplied.
@@ -61,6 +114,14 @@ trait Previous[@sp A] extends PartialPrevious[A] {
   override def partialPrevious(a: A): Option[A] = Some(previous(a))
 }
 
+object Previous {
+  def apply[A](implicit A: Previous[A]): Previous[A] =
+    A
+
+  implicit def catsKernelPreviousForBigInt: Previous[BigInt] =
+    cats.kernel.instances.bigInt.catsKernelStdOrderForBigInt
+}
+
 /**
  * A typeclass which has both `previous` and `next` operations
  * such that `next . previous == identity`.
@@ -70,6 +131,11 @@ trait UnboundedEnumerable[@sp A] extends Next[A] with Previous[A] {
   override def partialOrder: PartialOrder[A] = order
 }
 
+object UnboundedEnumerable {
+  def apply[A](implicit A: UnboundedEnumerable[A]): UnboundedEnumerable[A] =
+    A
+}
+
 trait BoundedEnumerable[@sp A] extends PartialPreviousUpperBounded[A] with PartialNextLowerBounded[A] {
 
   def order: Order[A]