Add missing trait.

diff --git a/src/ofc/generators/onetep/Tree.scala b/src/ofc/generators/onetep/Tree.scala
index c0b3ed85c65bcadf5dcece0775fa480ec6a6ce43..9f836ab7976bdf85f95e49581337b3d6c15362f4 100644 (file)
--- a/src/ofc/generators/onetep/Tree.scala
+++ b/src/ofc/generators/onetep/Tree.scala
@@ -5,6 +5,7 @@ import ofc.parser
 import ofc.parser.Identifier
 import ofc.InvalidInputException
 
+trait Index
 trait SpatialIndex extends Index
 trait DiscreteIndex extends Index