From: Harold Hausman <hhausman@...>
Date: 2007-03-25T08:54:57+09:00
Subject: Re: Ruby with C

On 3/25/07, dogwasstar@hotmail.com <dogwasstar@hotmail.com> wrote:
> Here is the C file
>
> static VALUE t_bit(VALUE self, VALUE obj)
> {
>     VALUE n;
>
>     n = NUM2INT(obj);
>     printf("Fun %d", INT2NUM(n));
>     return Qnil;
> }
>
>

Hi.

By putting the variable 'n' through the INT2NUM macro as you pass it
into printf you're re-converting it back into a Ruby VALUE which is
not what you want to do. It will give you unpredictable (or at least
more-difficult-to-predict ;) ) results...

Assuming you just want to print the value of 'obj' as an integer, you
should probably declare 'n' as an integer instead of as a VALUE, and
use the NUM2INT (as you have) to convert the Ruby VALUE 'obj' into a
plain int. Then you can pass it straight into printf (as you would
with any other int) ... no need for INT2NUM there.

hope that helps,
-Harold