From 5aa63d35ce0eb594f53dfddcfa4986e1de48d1a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Garc=C3=ADa=20Aubert?=
 <danielgarciaaubert@gmail.com>
Date: Wed, 4 Apr 2018 20:07:53 +0200
Subject: [PATCH] Add comments

---
 lib/cartodb/controllers/layergroup/tile.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/cartodb/controllers/layergroup/tile.js b/lib/cartodb/controllers/layergroup/tile.js
index 4008afa4..7837d116 100644
--- a/lib/cartodb/controllers/layergroup/tile.js
+++ b/lib/cartodb/controllers/layergroup/tile.js
@@ -41,7 +41,9 @@ module.exports = class TileLayergroupController {
     }
 
     register (mapRouter) {
+        // REGEXP matches with positive and negative numnbers
         const number = () => `(-?\\d+)`;
+        // REGEXP doesn't match with `val`
         const not = (val) => `(?!${val})([^\/]+?)`;
 
         mapRouter.get(