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-rw-r--r--tests/pos-scala2/viewtest1.scala42
1 files changed, 42 insertions, 0 deletions
diff --git a/tests/pos-scala2/viewtest1.scala b/tests/pos-scala2/viewtest1.scala
new file mode 100644
index 000000000..38945ad2f
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+++ b/tests/pos-scala2/viewtest1.scala
@@ -0,0 +1,42 @@
+package test
+
+trait Ordered[a] {
+ def < (x: a): Boolean
+}
+
+object O {
+ implicit def view (x: String): Ordered[String] = new Ordered[String] {
+ def < (y: String) = x.compareTo(y) < 0
+ }
+}
+
+object Empty extends Tree[Nothing]
+case class Node[c <% Ordered[c]](elem: c, l: Tree[c], r: Tree[c]) extends Tree[c]
+
+abstract class Tree[+a <% Ordered[a]] {
+ def insert[b >: a <% Ordered[b]](x: b): Tree[b] = this match {
+ case Empty =>
+ new Node(x, Empty, Empty)
+ case Node(elem, l, r) =>
+ if (x == elem) this
+ else if (x < elem) Node(elem, l insert x, r)
+ else Node(elem, l, r insert x)
+ }
+ def elements: List[a] = this match {
+ case Empty => List()
+ case Node(elem, l, r) =>
+ l.elements ::: List(elem) ::: r.elements
+ }
+}
+
+object Test {
+ import O.view
+
+ def main(args: Array[String]): Unit = {
+ var t: Tree[String] = Empty
+ for (s <- args) {
+ t = t insert s
+ }
+ println(t.elements)
+ }
+}