Squashed commit of the following:

commit 82d4905b9f61c1131577893e1ecb0215a35e01cc
Author: Jon <jonathan.j.mason@gmail.com>
Date:   Thu Dec 26 08:25:56 2013 -0600

    spec filter casting

commit a9925b841a10ef30b50e041de6724348fad31ef1
Author: Jon <jonathan.j.mason@gmail.com>
Date:   Thu Dec 26 08:20:28 2013 -0600

    cast filter argument