should work with undefined time

index.js

@@ -1,3 +1,5 @@
 module.exports = function time(ms, fn) {
-  return setTimeout(fn, ms)
+  return arguments.length === 1 
+       ? setTimeout(ms)
+       : setTimeout(fn, ms)
 }

test.js

@@ -10,4 +10,13 @@ describe('time', function() {
     time(75, function(){ expect(result).to.be.ok })
     time(99, done)
   })
+
+  it('should work with undefined time', function(done) {
+    var result = false
+      , fn = function(){ result = true }
+
+    time(fn)
+    time(5, function(){ expect(result).to.be.ok })
+    time(10, done)
+  })
 })