diff --git a/js/test.js b/js/test.js
index 2b57adb..cc9028b 100644
--- a/js/test.js
+++ b/js/test.js
@@ -5,8 +5,12 @@ function test_consts(args){
     let results = '<tr class=header><td>Const<td>Value<td>Test';
     for(const id in args['consts']){
         const label = args['consts'][id];
-        const value = globalThis.eval(label);
-        const result = value !== void 0;
+        let result = false;
+        let value = '';
+        try{
+            value = eval(label);
+            result = value !== void 0;
+        }catch{}
         results += '<tr ' + (!result ? ' style=background-color:#600' : '') + '>'
           + '<td>' + label
           + '<td>' + value