Arg._access is throwing an "Invalid calling object" for me in Internet Explorer (tested 8, 9, 10, 11) in cases where the value of selector was 0.

The error came from line 93 of arg-1.3.1.js:
if (typeof selector == 'string' || toString.call(selector) == '[object String]') {
This is a new one to me, but from what I can gather it's due to IE's implementation of toString not using Object.prototype .