Comment Apple Pascal on ProDOS (Score 1) 50
Good question. I have no idea how difficult that would be. It would depend on how well-factored the disk access routines are from the other OS routines. You *can* reserve part of a Profile hard disk as a Pascal volume using a tool that comes with Apple Pasca, but I don't know if that's a file on a ProDOS volum, or how it works.
The MS-DOS p-system did apparently interoperable with the FAT filesystem, so it's possibly do-able?