diff --git a/src/main/scala/leon/synthesis/Rules.scala b/src/main/scala/leon/synthesis/Rules.scala
index f0fb2e9c273f1a99f1d63d75e1fec9b52fecf8f2..b8ea78b0dcbe786e8d649afdae9b62a441250de9 100644
--- a/src/main/scala/leon/synthesis/Rules.scala
+++ b/src/main/scala/leon/synthesis/Rules.scala
@@ -3,6 +3,7 @@ package synthesis
 
 import purescala.Common._
 import purescala.Trees._
+import purescala.Extractors._
 import purescala.TreeOps._
 import purescala.TypeTrees._