diff options
| -rwxr-xr-x | src/library/scala/collection/LinearSeqOptimized.scala | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/src/library/scala/collection/LinearSeqOptimized.scala b/src/library/scala/collection/LinearSeqOptimized.scala index a28d796d5b..0f48d21b71 100755 --- a/src/library/scala/collection/LinearSeqOptimized.scala +++ b/src/library/scala/collection/LinearSeqOptimized.scala @@ -235,13 +235,16 @@ trait LinearSeqOptimized[+A, +Repr <: LinearSeqOptimized[A, Repr]] extends Linea override /*IterableLike*/ def sameElements[B >: A](that: GenIterable[B]): Boolean = that match { case that1: LinearSeq[_] => - var these = this - var those = that1 - while (!these.isEmpty && !those.isEmpty && these.head == those.head) { - these = these.tail - those = those.tail + // Probably immutable, so check reference identity first (it's quick anyway) + (this eq that1) || { + var these = this + var those = that1 + while (!these.isEmpty && !those.isEmpty && these.head == those.head) { + these = these.tail + those = those.tail + } + these.isEmpty && those.isEmpty } - these.isEmpty && those.isEmpty case _ => super.sameElements(that) } |