diff options
Diffstat (limited to 'src/library/scala/collection/immutable/Range.scala')
| -rw-r--r-- | src/library/scala/collection/immutable/Range.scala | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/src/library/scala/collection/immutable/Range.scala b/src/library/scala/collection/immutable/Range.scala index ca6720da19..d3fe367e50 100644 --- a/src/library/scala/collection/immutable/Range.scala +++ b/src/library/scala/collection/immutable/Range.scala @@ -57,8 +57,7 @@ import scala.collection.parallel.immutable.ParRange * and its complexity is O(1). */ @SerialVersionUID(7618862778670199309L) -@deprecatedInheritance("The implementation details of Range makes inheriting from it unwise.", "2.11.0") -class Range(val start: Int, val end: Int, val step: Int) +sealed class Range(val start: Int, val end: Int, val step: Int) extends scala.collection.AbstractSeq[Int] with IndexedSeq[Int] with scala.collection.CustomParallelizable[Int, ParRange] @@ -198,7 +197,24 @@ extends scala.collection.AbstractSeq[Int] copy(locationAfterN(n), end, step) } ) - + + /** Creates a new range containing the elements starting at `from` up to but not including `until`. + * + * $doesNotUseBuilders + * + * @param from the element at which to start + * @param until the element at which to end (not included in the range) + * @return a new range consisting of a contiguous interval of values in the old range + */ + override def slice(from: Int, until: Int): Range = + if (from <= 0) take(until) + else if (until >= numRangeElements && numRangeElements >= 0) drop(from) + else { + val fromValue = locationAfterN(from) + if (from >= until) newEmptyRange(fromValue) + else new Range.Inclusive(fromValue, locationAfterN(until-1), step) + } + /** Creates a new range containing all the elements of this range except the last one. * * $doesNotUseBuilders |