[texhax] where are latex functions defined?

[Robin Fairbairns]

> > Joe Cornelli said:
> >> Thank you - that was helpful.  Now for a follow up question,
> >> where are the TeX functions defined?
> 
> and Robin replied:
> > in the texbook or tex the program or ...
> >
> > http://www.tex.ac.uk/cgi-bin/texfaq2html?label=books+tutorials
> 
> There's also a file somewhere, which interweaves plain.tex w/ the 
> matching material from _The TeXbook_ so as to turn plain.tex into a 
> literate program (wonder how DEK forgot to do that ;), which while it 
> kind of skirts the matter of the license for _The TeXbook_ source, _is_ 
> kind of interesting to read.

it's on ctan in a rather curious fashion in web/tweb (tweb == "tex
web")

the directory includes tweb tools and wlodek bzyl's paper on tweb.
it also has an rcs directory with a checked-in copy of plain.tw, but
no "original" plain.tw

how that came to happen i don't know.  i know i was keen for bzyl's
stuff to go on ctan (having edited his tugboat paper), but that's as
far as i can remember.

robin