Tiny, tiny interpreter

I've yet to find a suitable scripting language for the Turtle. Its probably about time to consider rolling one of my own. I will probably use Tcl (circa 6.7) as a model. Rather than be "string" based, this language will be "array of byte" based, which will require some additional parsing. However, parse-on-the-fly model of early Tcl will be used (i.e. no intermediate byte code, no complex parse tree).