check semantic of defined and undefined variables implemented

do not check for built-in function
works on the example

1 files changed, 6 insertions, 0 deletions

diff --git a/src/ast/types/VoidType.java b/src/ast/types/VoidType.java
index d15933f..8e3f9b2 100644
--- a/src/ast/types/VoidType.java
+++ b/src/ast/types/VoidType.java
@@ -4,7 +4,13 @@ package ast.types;
  * A void type. Voids return nothing.
  */
 public class VoidType extends Type {
+
     public String toPrint(String prefix) {
         return prefix + "Void\n";
     }
+
+    @Override
+    public String toString() {
+        return "Void";
+    }
 }