Added more debug vsl

exercises/06/vslc/vsl_programs/ps3-simplify/lists.vsl

@@ -28,4 +28,6 @@ func main() begin
     if my_func(1, 2, 3, 5, 8, 13, 21, 34) > 3 then begin
         print "True!"
     end
+
+    return 0
 end

exercises/06/vslc/vsl_programs/ps3-simplify/while_test.vsl

@@ -0,0 +1,57 @@
+// This program is a simple test of while loops, counting down from 19 to 0
+// and skipping 10 (if continue is implemented)
+
+func while_test ()
+begin
+    var a, b
+    a := 20
+    
+    b := test_while()
+    
+    print a
+
+
+    if a > 0 then print "foobar"
+    while a > 0 do
+    begin
+        if a = 10 then
+        begin
+            a -= 1
+            print "Skip..."
+            continue
+        end
+        else
+            a -= 1
+        print a
+    end
+    return 0
+end
+
+func test_while()
+begin
+    var n, m
+
+    n := 4
+    m := 21
+
+    while n > 0 do
+    begin
+        n -= 1
+        if n = 2 then
+            continue
+
+        while m > 0 do
+        begin
+            m -= 1
+
+            if m = 10 then
+                continue
+
+            print n, m
+        end
+
+
+    end
+
+    return 0
+end