From: Logan Capaldo <logancapaldo@...>
Date: 2006-06-28T05:13:56+09:00
Subject: Re: Define External Superclass in a extension


On Jun 27, 2006, at 2:23 PM, Ceaser Larry 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
>

See rb_const_get. It'll be something like

rb_cMyClass = rb_define_class("MyClass",
                 rb_const_get(
                     rb_const_get(rb_cObject, intern("DBI")),
                     intern("BaseDriver")));