From: Harold Hausman <hhausman@...>
Date: 2007-02-18T01:07:00+09:00
Subject: Re: Using Ruby as an extension language

On 2/17/07, Harold Hausman <hhausman@gmail.com> wrote:
> And my other question comes from when I try to expose a new method to
> the running Ruby. Here are some snippets of my code:
> VALUE rb_myprint( VALUE inSelf, VALUE inString )
> {
>         // snip... but do stuff here, etc....
>         return Qnil;
> }
>
> and then later:
>         rb_define_global_function( "myprint", rb_myprint, 1 );
>
> 2. When I try to compile this, I get the following error:
> Error   2       error C2664: 'rb_define_global_function' : cannot convert
> parameter 2 from 'VALUE (__cdecl *)(VALUE,VALUE)' to 'VALUE (__cdecl
> *)(...)'        d:\code\littlecoder\littlecoder.cpp     68
>

So, I've found *an* answer to my question, but it feels a little nuts.
Anyone care to confirm that this is the best practice for exposing C++
static methods to Ruby?

typedef VALUE (*HOOK)(...);

///....
// define static functions, etc.....
///.....

rb_define_global_function( "myprint", reinterpret_cast<HOOK>(rb_myprint), 1 );

Man, ugly things like reinterpret_cast make me wish I was working with
a dynamic language... But that's the whole point of this exercise to
begin with, isn't it? :P

Many thanks for any input, and apologies for the answering myself noise.

-Harold