From 7341b0f478dd3d4a25a1d59609cf723ef3777bb2 Mon Sep 17 00:00:00 2001
From: Tom Russell <tomalrussell@gmail.com>
Date: Sat, 14 Apr 2018 09:30:40 +0100
Subject: [PATCH] Comment js, check before setup

---
 html/main.js | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/html/main.js b/html/main.js
index ad804d96..9aeb2357 100644
--- a/html/main.js
+++ b/html/main.js
@@ -1,6 +1,14 @@
-
-carousel = (function(){
+/**
+ * Simple carousel
+ *
+ * Based on example code by Christian Heilmann
+ * http://christianheilmann.com/2015/04/08/keeping-it-simple-coding-a-carousel/
+ */
+carousel = function(){
     var box = document.querySelector('.carousel');
+    if (!box) {
+        return
+    }
     var next = box.querySelector('.next');
     var prev = box.querySelector('.back');
     // Define the global counter, the items and the
@@ -33,4 +41,12 @@ carousel = (function(){
     // show the first element
     // (when direction is 0 counter doesn't change)
     navigate(0);
-})();
+}
+
+/**
+ * "Cut the mustard" and setup page
+ */
+if('querySelector' in document
+   && 'addEventListener' in window) {
+    carousel();
+}