1 
2 Testing existence
3 <?cs if:Color ?>
4   Color=Color (CORRECT)
5 <?cs else ?>
6   ERROR
7 <?cs /if ?>
8 
9 Testing not existence
10 <?cs if:!NoVar ?>
11   Correct, doesn't exist
12 <?cs else ?>
13   ERROR, doesn't exist
14 <?cs /if ?>
15 
16 <?cs if:NoVar ?>
17   ERROR, doesn't exist
18 <?cs else ?>
19   Correct, doesn't exist
20 <?cs /if ?>
21