From: Kaspar Schiess <eule@...>
Date: 2005-02-28T20:12:03+09:00
Subject: Re: structuring complexly-interdependent C/Ruby libraries

Hello Eric, 

Usually, you define classes in your C extension and likewise in your Ruby 
code, doing things twice, which does not matter since Ruby will take your 
meaning (creating one class). 

-- myclass.c
Init_... {
    	cMyClass = rb_define_class_under( mMyModule, "MyClass", rb_cObject ); 
}

-- myclass.rb
require 'myclass.so'
class MyClass
    	# ...
end

But yeah, redefinition with a different superclass gives you a 
SuperClassMismatch. So I would aim for different classes altogether, using 
mixins to mix the c code into the Ruby code: 

-- myclass.c
Init_... {
    	mMyClassMixin = rb_define_module_under( mMyModule, "MyClassCMixin" ); 
    	...
}

-- myclass.rb
require 'myclasscmixin'

class MyClass < MySuperClass
     	include MyClassCMixin
    	#...
end

This method is tested and works, and it looks clean enough to me. Now does 
this solve all your problems ? Yes, if I read you right. 

k

code manufacture & ruby lab at http://www.tua.ch/ruby
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