[TUHS] Typesetting ROFF/NROFF Documents

Hi everyone, I've cobbed together a crude Teletype Model 37 emulator that generates PDF files (https://github.com/TheBrokenPipe/Teletype-37-PDF) It produces sane-looking PDFs for most (all?) of the early UNIX ROFF/NROFF documents. The biggest advantage of this over something like "roff $1 | enscript -c -f Courier12 -l -M Letter --margins=67:-9:0:-9 -p $1.ps -s -0.05" is it supports half (forward/reverse) line feeds which enscript does not. Early ROFF stuff like the UNIX manuals and memos made extensive use of subscripts (and superscripts), making them rather painful to typeset. As an experiment, I re-set Ken Thompson's "Users' Reference to B" memo from early 1972 (https://github.com/TheBrokenPipe/kbman-reset) I picked this one because it contains a BNF-alike description of the grammar as well as fractions in code comments, both of which make extensive use of sub/superscripts. I went to the extent of overlaying the re-set pages on top of the originals to make sure everything lined up. I'd really appreciate it if someone could review my work on the B manual. If everything looks good, I may tackle other documents, starting with low hanging fruits like the "V0" manual and potentially moving on to re-setting the V1 and V2 manuals in the future (building on aap's work). Sincerely, Yufeng