diff -r b6ed836ce59b -r 484b74bc057e progs/detokenise.scala
--- a/progs/detokenise.scala	Mon Nov 18 11:11:11 2019 +0000
+++ b/progs/detokenise.scala	Wed Nov 20 17:10:03 2019 +0000
@@ -23,8 +23,11 @@
 case class T_STR(s: String) extends Token
 
 def deserialise[T](fname: String) : Try[T] = {
-  import scala.util.Using
-  Using(new ObjectInputStream(new FileInputStream(fname))) {
+  //import scala.util.Using
+  //Using(new ObjectInputStream(new FileInputStream(fname))) {
+  //  in => in.readObject.asInstanceOf[T]
+  //}
+  Try(new ObjectInputStream(new FileInputStream(fname))).get {
     in => in.readObject.asInstanceOf[T]
   }
 }