Re: luatex problems with texinfo.tex

[Karl Berry]

    Here's a file that I ran with pdftex and with luatex: both worked. 

Worked for me too (also tex and etex; xetex still fails, of course, but
that's ok).  Nice job.  I could ask my LuaTeX friends if we're missing
anything, but it looks straightforward.

My only comment is merely stylistic: for this tiny chunk of code, I'd be
tempted to just use the fully-qualified names (unicode.utf8.char,
string.byte, string.gsub) instead of defining and then using
abbreviations -- especially since they are only used once, I think.
But that's just me.

Thanks,
Karl