Don't build old simver docs

My old docs are build under a structure like the following: sources/jp/docs/swift/2.0.1/*. My goal is to not build a specific version of my docs, lets say 2.0.0, and below on each build. My goal is to use Middleman’s helpful ignore tool. I have tried adding something like ignore: sources/**/docs/**/#{ <1.9.9}/* This doesn’t work. Is anyone else doing this with success?