Refinements of "def seq" and murmurhash.

Trying to make hashcodes faster. Didn't achieve much on that front, so
redirected into structural/consistency issues. The latter was lacking
in terms of how/where "def seq" was defined. The documentation I can
find doesn't give me much hint that the sequential form of my sequential
collection might be a single-use iterator! (As in StringOps, ArrayOps.)
If that's intentional it should be in huge letters. I'm assuming for now
that it wasn't.

Also, there was this:

  GenMapLike:     def seq: Map[A, B]
  GenSetLike:     def seq: Set[A]
  GenSeqLike:     // nothing, returns Traversable

So I added some def seqs where I needed the more specific types for
my hashcode work. Hashcodewise, I broke the MurmurHash3 object into
a reusable class and a collections-specific object, and I deprecated
the methods which took GenTraversableOnce in favor of ones taking
TraversableOnce, because there's no reason the hashcode library should
have to know about things like "make sure to call seq before you
traverse or you'll be sorry." Exclude things by their type and you can
never make a mistake. End transmission.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/library/scala/collection/IndexedSeqLike.scala b/src/library/scala/collection/IndexedSeqLike.scala
index b743174260..baf5606ab5 100644
--- a/src/library/scala/collection/IndexedSeqLike.scala
+++ b/src/library/scala/collection/IndexedSeqLike.scala
@@ -6,8 +6,6 @@
 **                          |/                                          **
 \*                                                                      */
 
-
-
 package scala.collection
 
 import generic._
@@ -42,6 +40,9 @@ import scala.annotation.tailrec
 trait IndexedSeqLike[+A, +Repr] extends SeqLike[A, Repr] {
   self =>
 
+  def seq: IndexedSeq[A]
+  override def hashCode() = util.MurmurHash3.seqHash(seq)  // TODO - can we get faster via "indexedSeqHash" ?
+
   override protected[this] def thisCollection: IndexedSeq[A] = this.asInstanceOf[IndexedSeq[A]]
   override protected[this] def toCollection(repr: Repr): IndexedSeq[A] = repr.asInstanceOf[IndexedSeq[A]]
 
@@ -96,4 +97,3 @@ trait IndexedSeqLike[+A, +Repr] extends SeqLike[A, Repr] {
     result
   }
 }
-