New subtype constraint maintenance algorithm.

Objective: Avoid cycles by detecting all cases where

    A <: B and B <: A

and removing those cases by unifuing A and B.

Cycles need to be avoided because they lead to deep subtype recursions.

1 files changed, 5 insertions, 0 deletions

diff --git a/tests/pos/typers.scala b/tests/pos/typers.scala
index c02bcda22..1626731bd 100644
--- a/tests/pos/typers.scala
+++ b/tests/pos/typers.scala
@@ -4,6 +4,11 @@ import annotation.{tailrec, switch}
 import collection.mutable._
 
 object typers {
+  
+  val entries = Array("abc", "def")
+  
+  for ((x, i) <- entries.zipWithIndex)
+    println(x)
     
   object Eta {