From 89bacb9c25a58454ff1878e67f7ea07ffc8c269f Mon Sep 17 00:00:00 2001 From: Dmitry Petrashko Date: Tue, 12 May 2015 18:30:53 +0200 Subject: Run tests as they were in scala. --- tests/pending/run/t3346e.scala | 81 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 tests/pending/run/t3346e.scala (limited to 'tests/pending/run/t3346e.scala') diff --git a/tests/pending/run/t3346e.scala b/tests/pending/run/t3346e.scala new file mode 100644 index 000000000..ac0de564d --- /dev/null +++ b/tests/pending/run/t3346e.scala @@ -0,0 +1,81 @@ +import scala.language.implicitConversions +import scala.collection.generic.CanBuildFrom +import scala.math.Ordering +import collection.{TraversableLike, SeqLike} +import collection.immutable.BitSet + +class QuickSort[Coll](a: Coll) { + //should be able to sort only something with defined order (someting like a Seq) + def quickSort[T](implicit ev0: Coll => SeqLike[T, Coll], + cbf: CanBuildFrom[Coll, T, Coll], + n: Ordering[T]): Coll = { + quickSortAnything(ev0, cbf, n) + } + + //we can even sort a Set, if we really want to + def quickSortAnything[T](implicit ev0: Coll => TraversableLike[T, Coll], + cbf: CanBuildFrom[Coll, T, Coll], + n: Ordering[T]): Coll = { + import n._ + if (a.size < 2) { + a + } else { + // We pick the first value for the pivot. + val pivot = a.head + val (lower, tmp) = a.partition(_ < pivot) + val (upper, same) = tmp.partition(_ > pivot) + val b = cbf() + b.sizeHint(a.size) + b ++= new QuickSort(lower).quickSortAnything + b ++= same + b ++= new QuickSort(upper).quickSortAnything + b.result + } + } +} + +class FilterMap[Repr](a: Repr) { + def filterMap[A, B, That](f: A => Option[B])(implicit ev0: Repr => TraversableLike[A, Repr], + cbf: CanBuildFrom[Repr, B, That]): That = { + a.flatMap(e => f(e).toSeq) + } +} + +class FilterMapFixed[A, Repr <% TraversableLike[A, Repr]](a: Repr) { + def filterMap2[B, That](f: A => Option[B])(implicit cbf: CanBuildFrom[Repr, B, That]): That = { + a.flatMap(e => f(e).toSeq) + } +} + +object MyEnhancements { + implicit def toQS[Coll](a: Coll) = new QuickSort(a) + implicit def toFM[Coll](a: Coll) = new FilterMap(a) + implicit def toFM2[A, Repr <% TraversableLike[A, Repr]](a: Repr) = new FilterMapFixed(a) +} + +object Test extends App { + + import MyEnhancements._ + + println("qwe".quickSort) + println(Array(2, 0).quickSort.toList) + println(Seq(2, 0).quickSort) + //not very useful to sort a set, but just as a demonstration + println(BitSet(2, 0).quickSortAnything) + + //need to hint type inferencer, + //probably will be able to overcome after https://issues.scala-lang.org/browse/SI-4699 and + // related issues are fixed (by moving ev0 parameter from filterMap to toFM), see toFM2 + println("qwe".filterMap((c: Char) => Some(c.toInt))) + println("qwe".filterMap((c: Char) => Some(c))) + println(Array(2, 0).filterMap((c: Int) => Some(c.toInt)).toList) + println(Seq(2, 0).filterMap((c: Int) => if (c < 2) Some(c + "!") else None)) + def test(i:Int) = Option(i) + println(BitSet(2,0).filterMap(test)) + + println(toFM2("qwe").filterMap2(c => Some(c))) + println(toFM2(Array(2, 0)).filterMap2(c => Some(c.toInt)).toList) + //No implicit view available from java.lang.String => scala.collection.TraversableLike[A,java.lang.String]. :( + //Not anymore :) + println("qwe".filterMap2(c => Some(c))) +} -- cgit v1.2.3