Printing

1 files changed, 4 insertions, 1 deletions

diff --git a/BStack.dcl b/BStack.dcl
index 4095f60..95cf86e 100644
--- a/BStack.dcl
+++ b/BStack.dcl
@@ -1,17 +1,20 @@
 definition module ABC.BStack
 
-from StdOverloaded import class ==
+from StdOverloaded import class ==, class toString
 from ABC.Def import ::NrArgs
 
 :: Basic   = Int  Int
            | Bool Bool
 
 instance == Basic
+instance toString Basic
 
 :: BSrc    :== Int
 :: BDst    :== Int
 :: BStack (:== [Basic])
 
+instance toString BStack
+
 bs_copy   :: BSrc BStack -> BStack
 bs_get    :: BSrc BStack -> Basic
 bs_getB   :: BSrc BStack -> Bool