I had a passing though of writing emulators for the machines found in an old record unit shop, Card Punches - would be something like an editor. Sorters, Collators?, and all the other machines, with text files as card-decks. I have the link on Wikipeadea, it also just gives a gloss overview. I am not finding the detail needed. Never mind, it wasn't important. I'll go on to other things.