diff --git a/run-exp.py b/run-exp.py
index fe326a5d3261cf9f45a7616fb0aab55d05a80f64..916f2ed09de1ee78dd578a2b393e32bdefc24a5f 100755
--- a/run-exp.py
+++ b/run-exp.py
@@ -90,6 +90,12 @@ class Task:
                 if v not in variables.keys() or (isinstance(variables[v], bool) and not variables[v]):
                     continue  # skip
 
+            if "if-not-variable" in p:
+                v = p["if-not-variable"]
+
+                if v in variables.keys() and (not isinstance(variables[v], bool) or variables[v]):
+                    continue  # skip
+
             args.append(p["value"].format(**variables))
 
         # print()