diff --git a/doc/src/js/configure.js b/doc/src/js/configure.js
index 1d7f572..d14eba8 100644
--- a/doc/src/js/configure.js
+++ b/doc/src/js/configure.js
@@ -1,4 +1,6 @@
-$( document ).ready(function() {
-    console.log("Configure hljs");
-    hljs.configure({languages:['cpp']});
-});
+if (typeof $ === "function"){ 
+    $( document ).ready(function() {
+        console.log("Configure hljs");
+        hljs.configure({languages:['cpp']});
+    });
+}