From: Ben Thomas <ben.thomas@...>
Date: 2003-02-26T04:42:57+09:00
Subject: Re: General question about args (embedded code)

Yukihiro Matsumoto wrote:
> Hi,
> 
> In message "Re: General question about args (embedded code)"
>     on 03/02/26, Ben Thomas <ben.thomas@wickedstudios.com> writes:
> 
> |When I debugged my example, the second argument is never passed to 
> |rb_const_get function. After I read the code of rb_protect, I though it 
> |was normal that this code doesn't work since rb_protect only pass 1 
> |arguments to the function it's calling. But I'm not an expert in pure C, 
> |so I was thinking that maybe I'm missing something, that there was a way 
> |to pass many arguments without using helper functions...
> 
> So you're expecting rb_const_get() to receive two arguments.  Hmm,
> rb_protect() calls its function argument with single argument, you
> have to unpack by yourself, i.e.
> 
>   static VALUE
>   cget(VALUE *args)
>   {
>      return rb_const_get(args[0], (ID)args[1]);
>   }
> 
>   void
>   foo()
>   {
>       VALUE args[2];
>       args[0] = rb_cObject;
>       args[1] = rb_intern("Foo");
> 
>       rb_protect(cget, args, &result);
>   }
> 
> Do you get it?
> 
> 							matz.
> 
> 

Yep, and it works just fine!

Thankx for the answer!
Ben.