[mrbald]

"make sure it's something that can actually be checked" -- I'd love to find out about a sane (not purely academic, financially viable) way to do it. Since university days I know that a piece of paper is an irreplaceable tool - cheap and universal. I usually just draw it on paper, then code, then fix the code, then update the painting, and do it over again until both match each other and work. Never fails me.