From: Riley Lynch <riley@...>
Date: 2001-10-30T19:47:59+09:00
Subject: [ruby-talk:23827] Global variables and Qfalse

Here's a curiosity:

When I set a global variable to Qfalse in c (rb_define_variable), 
it returns invariably as Qnil -- even on the ruby side. 

This problem arises in the var_getter callback ("variable.c") which
is assigned the the global_entry in rb_defined_hooked_variable. 
var_getter reads in part:

  if (!var || !*var) return Qnil;

..which explains what is happening, since "var", in this case is 
a pointer to a VALUE set to Qfalse, i.e. 0.

I understand why a null VALUE pointer is being returned as as nil
object, but I don't follow the rationale for making the same 
transformation on a pointer to Qfalse. Is there a case for this
behavior?

Thanks,

--Riley