diff --git a/IDE/src/util/DefinesSet.bf b/IDE/src/util/DefinesSet.bf
index 44f599d3..d55feafa 100644
--- a/IDE/src/util/DefinesSet.bf
+++ b/IDE/src/util/DefinesSet.bf
@@ -18,7 +18,7 @@ namespace IDE.util
 				return;
 			}
 
-			if (!mDefinesSet.ContainsWith(str))
+			if (!mDefinesSet.ContainsAlt(str))
 			{
 				var strCopy = new String(str);
 				mDefines.Add(strCopy);