cosmetic changes to liftables

Namely:
1) Moved definitions of Liftable and Unliftable into a separate file.
2) Inlined internal names that were only used in StandardLiftables.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/reflect/scala/reflect/api/Liftables.scala b/src/reflect/scala/reflect/api/Liftables.scala
new file mode 100644
index 0000000000..6ac5557caa
--- /dev/null
+++ b/src/reflect/scala/reflect/api/Liftables.scala
@@ -0,0 +1,30 @@
+package scala
+package reflect
+package api
+
+// TODO: needs a Scaladoc
+trait Liftables { self: Universe =>
+
+  // TODO: needs a Scaladoc
+  trait Liftable[T] {
+    def apply(value: T): Tree
+  }
+
+  // TODO: needs a Scaladoc
+  object Liftable extends StandardLiftableInstances {
+    def apply[T](f: T => Tree): Liftable[T] =
+      new Liftable[T] { def apply(value: T): Tree = f(value) }
+  }
+
+  // TODO: needs a Scaladoc
+  trait Unliftable[T] {
+    def unapply(tree: Tree): Option[T]
+  }
+
+  // TODO: needs a Scaladoc
+  object Unliftable extends StandardUnliftableInstances {
+    def apply[T](pf: PartialFunction[Tree, T]): Unliftable[T] = new Unliftable[T] {
+      def unapply(value: Tree): Option[T] = pf.lift(value)
+    }
+  }
+}