Exclude JS source code from the output

_javascript/utils/lang-badge.js

@@ -0,0 +1,20 @@
+/**
+ *  Add language indicator to code snippets
+ */
+
+$(function() {
+  const prefix = "language-";
+  const regex = new RegExp(`^${prefix}([a-z])+$`);
+
+  $(`div[class^=${prefix}`).each(function() {
+    let classes = $(this).attr("class").split(" ");
+
+    classes.forEach((_class) => {
+      if (regex.test(_class)) {
+        let lang = _class.substring(prefix.length);
+        $(this).attr("lang", `${lang}`);
+      }
+    });
+
+  });
+});