Preparations for new version of AbstractPartial...

Preparations for new version of AbstractPartialFunctions that also does
isDefinedAt correctly. Should be a new starr. Review by extempore.

2 files changed, 10 insertions, 2 deletions

diff --git a/src/library/scala/PartialFunction.scala b/src/library/scala/PartialFunction.scala
index ac721b88bc..254a610648 100644
--- a/src/library/scala/PartialFunction.scala
+++ b/src/library/scala/PartialFunction.scala
@@ -48,6 +48,9 @@ trait PartialFunction[-A, +B] extends (A => B) {
         else that.apply(x)
     }
 
+  def orElseFast[A1 <: A, B1 >: B](that: PartialFunction[A1, B1]) : PartialFunction[A1, B1] =
+    orElse(that)
+
   /**  Composes this partial function with a transformation function that
    *   gets applied to results of this partial function.
    *   @param  k  the transformation function
@@ -90,6 +93,7 @@ object PartialFunction {
     def isDefinedAt(x: Any) = false
     def apply(x: Any): Nothing = throw new MatchError(x)
     override def orElse[A1, B1](that: PartialFunction[A1, B1]): PartialFunction[A1, B1] = that
+    override def orElseFast[A1, B1](that: PartialFunction[A1, B1]): PartialFunction[A1, B1] = that
     override def lift = (x: Any) => None
   }
   def empty[A, B] : PartialFunction[A, B] = empty_pf
diff --git a/src/library/scala/runtime/AbstractPartialFunction.scala b/src/library/scala/runtime/AbstractPartialFunction.scala
index 2a45ec3671..b188cbb37d 100644
--- a/src/library/scala/runtime/AbstractPartialFunction.scala
+++ b/src/library/scala/runtime/AbstractPartialFunction.scala
@@ -32,11 +32,15 @@ abstract class AbstractPartialFunction[-T1, +R]
   // Question: Need to ensure that fallBack is overwritten before any access
   // Is the `synchronized` here the right thing to achieve this?
   // Is there a cheaper way?
-  def orElseFast[A1 <: T1, B1 >: R](that: PartialFunction[A1, B1]) : PartialFunction[A1, B1] = {
+  override def orElseFast[A1 <: T1, B1 >: R](that: PartialFunction[A1, B1]) : PartialFunction[A1, B1] = {
     val result = this.clone.asInstanceOf[AbstractPartialFunction[A1, B1]]
     result.synchronized {
-      result.fallBack = this.fallBack orElse that
+      result.fallBack = this.fallBack orElseFast that
       result
     }
   }
+/*
+  def isDefinedAt(x: T1): scala.Boolean = isDefinedAtCurrent(x) || fallBack.isDefinedAt(x)
+  def isDefinedAtCurrent(x: T1): scala.Boolean = false
+*/
 }