What *is* the preferred indentation style for ruby core C code?

After combing through a few hundred lines of ruby core and noticing matz
himself using tabs for indentation where most everything else is space
indentation(`svn -r PREV diff io.c` + vim :set list, which I was going
to fix as a cosmetic patch), and then after reading every ruby-forum
post with the word 'tab' in it (including some lengthy, lightly veiled
editor wars ;-) ), well, I have to ask that question.

The closest thing I could find was SASADA Kolchi's reference "This
indent rule is Ruby's", which I think is referring to the regular 2
spaces for .rb code, not C code.

[BTW, I am praying as hard as I can that the answer is not anything that
mixes both tabs and spaces, which reek havoc on any multi-page printing
possibilities, which I was hoping to do for 'light bed-time
reading' ;-)]

May I humbly suggest whatever the ri indentation style guideline is be
posted to "Rules for Core Developers".

http://www.ruby-lang.org/en/community/ruby-core/

I will be the first to volunteer to help to do some time as a
code-cleaner and get some cosmetic patches ready. A lot, but not all, of
this amounts to little more than `ruby -p -i -e 'gsub(/\t/, "  ")' io.c`
for example. Of course we'd have to check the diffs sticking to one file
at a time making sure stuff still compiles if nothing else.

>Steven Swerling wrote:
>> Since you're asking... The yarv c files have a strange indenting scheme
>> (2 spaces, then tabs after that). I couldn't figure out how to configure
>> my Tab settings to fix it up. Would it be possible to switch to all
>> spaces (or only Tabs), and reformat? Trying to read a method like
>> "iseq_compile_each" without proper formatting is really hard.
> 
> Never mind -- set tabstop=8.
>
>This indent rule is Ruby's.

>In fact, I love only 2 space indentation, but I compromised to use it.

-- 
Rob Muhlestein
http://rob.muhlestein.net