From: Tobias Grimm <listaccount@...>
Date: 2004-08-26T08:08:06+09:00
Subject: rb_rescue2 - throwing exception in rescue_func

Hi!

I still have some problems with embedding Ruby in an application.

SWIG uses rb_rescue2() to invoke methods. Now I would like to throw
a C++ exception, if Ruby raises any exception. SWIG puts this throw
statement in the rescue_func function passed to rb_rescue2().

But for some reason, I can't catch this exception from my C++ application.
(See the small sample code at the end... the exception never gets caught. It
somehow gets lost in rb_rescue())

Is it simply not possible to "transform" a Ruby exception into a C++
exception using rb_rescue2()? Will I have to rewrite SWIG to use rb_protect()?

bye,

Tobias



#include <ruby.h>
#include <iostream>

VALUE begin_func(VALUE begin_func_args)
{
     return rb_funcall(begin_func_args, rb_intern("givemeanerror"), 0, NULL);
}


VALUE rescue_func(VALUE rescue_func_args, VALUE error_info)
{
     cerr << "throwing exception" << endl;
     throw "exception";
}

int main()
{
     ruby_init();

     try {
	rb_rescue((VALUE(*)(ANYARGS)) begin_func, Qnil,
           (VALUE(*)(ANYARGS)) rescue_func, Qnil);
     }
     catch (...) {
	cerr << "exception caught" << endl ;
     }

     ruby_finalize();

     return 0;
}