Making "docker run ... bash" Remember

Here's a small docker+shell hack I've never seen around and feel it makes a difference if you're getting in and out different (but related) containers. Very hackish, but works surprisingly well! Don't try it at home or rely on anything from it for other tools, as it doesn't compose very well, but hey... it's free :)

It's shell monkeypatching, and some kind of command parsing that looks like tcl/lisp-y list munging. Enjoy!