ct: Allow body to be optional in db.atomic.
diff --git a/lib/nano.js b/lib/nano.js
index 9ca5137..797a8b5 100644
--- a/lib/nano.js
+++ b/lib/nano.js
@@ -556,6 +556,10 @@
 
     // http://docs.couchdb.org/en/latest/api/ddoc/render.html#put--db-_design-ddoc-_update-func-docid
     function updateWithHandler(ddoc, viewName, docName, body, callback) {
+      if (typeof body === 'function') {
+          callback = body;
+          body = undefined;
+      }
       return view(ddoc, viewName + '/' + encodeURIComponent(docName), {
         type: 'update',
         method: 'PUT',