1 files changed, 1 insertions, 0 deletions
diff --git a/While.dcl b/While.dcl
index aeb685d..2440457 100644
--- a/While.dcl
+++ b/While.dcl
@@ -19,6 +19,7 @@ instance toState State
 instance toState CharState
 
 instance toString ArithExpr
+instance toString Bool
 instance toString BoolExpr
 instance toString Stm
 instance toString Var