diff options
| -rw-r--r-- | src/library/scala/util/hashing/MurmurHash3.scala | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/src/library/scala/util/hashing/MurmurHash3.scala b/src/library/scala/util/hashing/MurmurHash3.scala index 3efd5b5e72..1cfb8276fe 100644 --- a/src/library/scala/util/hashing/MurmurHash3.scala +++ b/src/library/scala/util/hashing/MurmurHash3.scala @@ -157,6 +157,20 @@ private[hashing] class MurmurHash3 { // Finalization finalizeHash(h, data.length) } + + final def listHash(xs: collection.immutable.List[_], seed: Int): Int = { + var n = 0 + var h = seed + var elems = xs + while (!elems.isEmpty) { + val head = elems.head + val tail = elems.tail + h = mix(h, head.##) + n += 1 + elems = tail + } + finalizeHash(h, n) + } } /** @@ -199,7 +213,11 @@ object MurmurHash3 extends MurmurHash3 { /** To offer some potential for optimization. */ - def seqHash(xs: collection.Seq[_]): Int = orderedHash(xs, seqSeed) + def seqHash(xs: collection.Seq[_]): Int = xs match { + case xs: List[_] => listHash(xs, seqSeed) + case xs => orderedHash(xs, seqSeed) + } + def mapHash(xs: collection.Map[_, _]): Int = unorderedHash(xs, mapSeed) def setHash(xs: collection.Set[_]): Int = unorderedHash(xs, setSeed) |