From: nobuyoshi nakada <nobuyoshi.nakada@...>
Date: 2005-12-27T12:50:36+09:00
Subject: Re: global rb_funcall

Hi,

At Tue, 27 Dec 2005 07:55:32 +0900,
Eero Saynatkari wrote in [ruby-talk:172589]:
> > i'm embedding ruby into a C++, how do i call _global_ functions from C?
> > 
> > like
> > 
> >    rb_funcall2(??, rb_intern("test"), 0, NULL);
> > 
> > thanks
> 
> All of the global methods become singleton methods of
> the top-level Object object, so you should be able to
> refer to rb_cObject (I am unable to test). If that
> does not work, see if README.EXT provides any clues.

They are private instance methods of Object.

  $ ruby -e 'def foo;end; p Object.private_instance_methods.grep(/foo/)'
  ["foo"]

So the receiver is not a matter,

  rb_funcall2(Qnil, rb_intern("test"), 0, NULL);
  rb_funcall2(INT2FIX(999), rb_intern("test"), 0, NULL);
  rb_funcall2(rb_cArray, rb_intern("test"), 0, NULL);
  rb_funcall2(rb_str_new(0, 0), rb_intern("test"), 0, NULL);
  rb_funcall2(rb_ary_new(), rb_intern("test"), 0, NULL);
  rb_funcall2(rb_hash_new(), rb_intern("test"), 0, NULL);
  rb_funcall2(rb_module_new(), rb_intern("test"), 0, NULL);

all work.

-- 
Nobu Nakada