improve integration of DenseVector into collection framework:

* factor out similarities between *Wrapped and *Ops to *Like
* remove custom builder (use array buffer instead sonce DenseVectors are backed by arrays)
* refactor CanBuildFroms
* make LowPriority implicits to a trait

1 files changed, 24 insertions, 8 deletions

diff --git a/src/main/scala/scalam/collection/DenseVectorOps.scala b/src/main/scala/scalam/collection/DenseVectorOps.scala
index b7b6446..7f8e9f9 100644
--- a/src/main/scala/scalam/collection/DenseVectorOps.scala
+++ b/src/main/scala/scalam/collection/DenseVectorOps.scala
@@ -1,16 +1,32 @@
 package scalam.collection
 
-import scala.collection.mutable.IndexedSeqOptimized
 import breeze.linalg.DenseVector
+import scala.collection.mutable.ArrayBuffer
+import scala.collection.generic.CanBuildFrom
+import scala.collection.mutable.Builder
 
 /* TODO find solution to remove class manifest */
-class DenseVectorOps[Elem: ClassManifest](self: DenseVector[Elem]) extends IndexedSeqOptimized/*Like*/[Elem, DenseVector[Elem]] {
-  override def newBuilder = new DenseVectorBuilder[Elem]
+class DenseVectorOps[Elem: ClassManifest](override val repr: DenseVector[Elem]) extends DenseVectorLike[Elem, DenseVector[Elem]] {
+  val self = repr
+  def newBuilder = DenseVectorOps.newBuilder[Elem]
   
-  override def apply(index: Int) = self.apply(index)
-  override def update(index: Int, value: Elem) = self.update(index, value)
-  override def length = self.length
-  
-  override def seq = this
+  override protected[this] def thisCollection = new WrappedDenseVector(self)
+  override protected[this] def toCollection(repr: DenseVector[Elem]): WrappedDenseVector[Elem] = new WrappedDenseVector(repr)
+  override def seq = thisCollection
 }
 
+object DenseVectorOps {
+  def newBuilder[Elem: ClassManifest] = new ArrayBuffer[Elem]  mapResult (x => new DenseVector(x.toArray))
+  
+  implicit def canBuildFrom[T: ClassManifest] = new CanBuildFrom[DenseVector[_], T, DenseVector[T]] {
+    def apply(from: DenseVector[_]): Builder[T, DenseVector[T]] = newBuilder[T]
+    def apply: Builder[T, DenseVector[T]] = newBuilder[T]
+  }
+  /*
+   implicit def denseVectorBuildFrom[A: ClassManifest]: CanBuildFrom[DenseVector[_], A, DenseVector[A]] =
+    new CanBuildFrom[DenseVector[_], A, DenseVector[A]] {
+      def apply(from: DenseVector[_]): Builder[A, DenseVector[A]] = apply()
+      def apply(): Builder[A, DenseVector[A]] = collection.DenseVectorOps.newBuilder[A]
+    }
+    */
+}