From: Tim Pease <tim.pease@...>
Date: 2006-06-28T05:10:43+09:00
Subject: Re: Define External Superclass in a extension

This has worked for me in the past ...


VALUE tmp, your_class;

rb_require( "dbi" );

tmp = rb_const_get( rb_cObject, rb_intern("DBI") );
tmp = rb_const_get( tmp, rb_intern("BaseDriver") );

your_class = rb_define_class( "YourClass", tmp );


The rb_require used above will not work for gems.  You'll have to call
the require method of the Gem module to load gems.

Blessings,
Tim Pease



On 6/27/06, Ceaser Larry <ceaserlarry@mac.com> wrote:
> I'm trying to learn how to create a ruby extension. I've read the
> pick axe book but I'm running into a problem understanding how to get
> a reference to classes defined outside the ruby.h header.
>
> My problem is how do I reference the DBI::BaseDriver as a super class
> to my object?
>
> In C I understand I can use the following to define a new class
>
> VALUE rb_cMyClass = rb_define_class("MyClass", rb_cObject)
>
> somehow I need to replace rb_cObject with a reference to the
> DBI::BaseDriver like so
>
> VALUE rb_cMyClass = rb_define_class("MyClass", [DBI::BaseDriver])
>
> Any help or nudge in the right direction would be appreciated.
>
> Thanks
> Ceaser
>
>