From: daz <dooby@...10.karoo.co.uk>
Date: 2004-06-05T17:48:38+09:00
Subject: Re: Extending in C:  need to use a non-basic class defined in Ruby in my C code


Austin McDonald wrote:
> Hi, I'm attempting to transfer some intensive functions from Ruby to C,
> but I'd like to put as little of my code in C as possible.  So, I'm
> trying to access a class defined entirely in Ruby from my C code.
> Specifically, I need to create an instance of this class (called
> Population) and access some of its methods.  A few questions about this:
>
> 1) Do the functions I need to use have to be implemented in C as well,
> or can I access their "ruby version" using some C functions?  What C
> functions do I need to use to do this?
>

Seemless beauty is what you'll find :-)
Define an empty class (if its name is known) in the Init_foo part of
your extension - look at any other extension to get clues (rb_define_class).

Reopen your class (looks the same as a class definition) and define
your methods inside it (all in Ruby):

class Foo
  def a
    # whatever
  end

  def b
  end
end

Call them from C using the rb_funcall family.

> 2)  Is there a decent C API document anywhere?  I've read through
> "Programming Ruby," and its chapter on extending in C seems adequate for
> getting started, but leaves out a lot and simply refers one to the
> horribly unreadable header files, which give little to no indication as
> to what each function does.
>

Co-author of "Programming Ruby," (and so much more relating to Ruby)
Dave Thomas has documented the API in the .c files if you grab a
reasonably up-to-date copy of the source distribution.

> And, on a related note:
>
> 3)  What kind of IDE have you found to be good for co-development of
> Ruby/C code?  I'm currently working with Dev-C++ (www.bloodshed.net),
> and with some tweaking it seems usable.  Is there anything better?

Ooooh, that was sneaky; you just want to ensure that this thread
grows to 35+ replies, but the downside is that no-one gets round
to answering your main questions.
My answer is:  You /know/ there are better IDE's that Dev-C++, even free
ones, but there isn't just one for Ruby and I use a low-priced
shareware one on Windows which is an anagram of UtralEdti and has
ctag support, macros, blah ... Everyone else uses their favourite
and they're all better than mine, OK.

>
> Thanks very much,
>

Thank you for choosing Ruby ;-)


daz