From: Stefano Crocco <stefano.crocco@...>
Date: 2007-09-28T16:21:49+09:00
Subject: Re: Making 'new' private in a C extension.

Alle gioved� 27 settembre 2007, alterego@sdf.lonestar.org ha scritto:
> Hello all,
>
>   I'm writing a C extension, one of the classes I define can only be
> instantiated via a defined 'get_instance' singleton method. This method
> will only ever return one instance, that is, successive calls will always
> return exactly the same ruby object.
>
>   My problem is that someone could still call 'new' on the class. I'd like
> to remove that possibility by making 'new' private. Unfortunately I can't
> for the life of me work out how.
>
>   Any help on this subject will be much appreciated. - Tom
>
> =============
>   Go Burma!
> =============

I think you need to use the C function rb_mod_private_method, defined in 
eval.c, which corresponds to the ruby method Module.private_class_method. But 
I think you can use the Singleton module provided with ruby: include it in 
your class and you get a class of which only an instance can exist. From the 
C code, you can use the function rb_mod_include.

I hope this helps

Stefano