From 6e1f049456cf6bfd56b016467616280b8e3225e3 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Tue, 30 Apr 2013 21:33:55 +0200
Subject: [PATCH] Improve type checking in ol.source.StaticImage

---
 src/ol/source/staticimagesource.js | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/ol/source/staticimagesource.js b/src/ol/source/staticimagesource.js
index 74dd079a63..17791719fd 100644
--- a/src/ol/source/staticimagesource.js
+++ b/src/ol/source/staticimagesource.js
@@ -60,7 +60,14 @@ ol.source.StaticImage.prototype.getImage =
  * @return {ol.ImageUrlFunctionType} Function.
  */
 ol.source.StaticImage.createImageFunction = function(url) {
-  return function(extent, size, projection) {
-    return url;
-  };
+  return (
+      /**
+       * @param {ol.Extent} extent Extent.
+       * @param {ol.Size} size Size.
+       * @param {ol.Projection} projection Projection.
+       * @return {string|undefined} URL.
+       */
+      function(extent, size, projection) {
+        return url;
+      });
 };