Anyway here's my 45-line code for a harness that reads in lines of ASCII numbers and prints and dumps the stack after each.
It's… awkward in places. It would have helped to have else-if, character literals for whitespace (like '\t' and '\r'), and a better story for complex boolean exps
(`DUP DUP DUP 9 = SWAP 13 = OR SWAP 32 = OR`. Ouch.) Parts feel nice and parts feel real bad.
I expect the ACTUAL PROGRAM will be a few lines long, and possibly only take mere minutes.