Add Order->Ordering implicit conversion to implicits, instances

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

@@ -20,3 +20,4 @@ trait AllInstances
   with    TupleInstances
   with    UUIDInstances
   with    SymbolInstances
+  with    OrderInstances

core/src/main/scala/cats/instances/order.scala

@@ -0,0 +1,5 @@
+package cats
+package instances
+
+trait OrderInstances extends cats.kernel.OrderToOrderingConversion
+

core/src/main/scala/cats/instances/package.scala

@@ -32,4 +32,5 @@ package object instances {
   object try_       extends TryInstances
   object tuple      extends TupleInstances
   object uuid       extends UUIDInstances
+  object order      extends OrderInstances
 }

kernel/src/main/scala/cats/kernel/Order.scala

@@ -139,7 +139,16 @@ abstract class OrderFunctions[O[T] <: Order[T]] extends PartialOrderFunctions[O]
     ev.max(x, y)
 }
 
-object Order extends OrderFunctions[Order] {
+trait OrderToOrderingConversion {
+  /**
+   * Implicitly convert a `Order[A]` to a `scala.math.Ordering[A]`
+   * instance.
+   */
+  implicit final def catsKernelOrderingForOrder[A](implicit ev: Order[A]): Ordering[A] =
+    ev.toOrdering
+}
+
+object Order extends OrderFunctions[Order] with OrderToOrderingConversion {
   /**
    * Access an implicit `Order[A]`.
    */
@@ -160,13 +169,6 @@ object Order extends OrderFunctions[Order] {
       def compare(x: A, y: A) = f(x, y)
     }
 
-  /**
-   * Implicitly convert a `Order[A]` to a `scala.math.Ordering[A]`
-   * instance.
-   */
-  implicit def catsKernelOrderingForOrder[A](implicit ev: Order[A]): Ordering[A] =
-    ev.toOrdering
-
   /**
    * An `Order` instance that considers all `A` instances to be equal.
    */