Re: [Boost-users] [exception] Using Boost.Exception infrastructure without using boost::exception

On Sat, 28 May 2011 21:57:34 -0700, Emil Dotchevski wrote:

On Sat, May 28, 2011 at 9:50 PM, Mostafa wrote:

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On Sat, 28 May 2011 21:01:56 -0700, Emil Dotchevski wrote:

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On Sat, May 28, 2011 at 8:37 PM, Mostafa wrote:

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All of the Boost Exception functionality works only if the exceptions derive from boost::exception. Your only two choices are to do it explicitly or to call boost::throw_exception which does it for you.

It seems that some functionality doesn't, namely boost::enable_current_exception, and I was hoping to leverage such functionality to achieve my aforementioned goal.

boost::enable_current_exception enables the boost::current_exception/boost::exception_ptr support by returning an object that derives from boost::exception *and* the type of the passed object.

Therefore:

throw boost::enable_current_exception(my_exception());

satisfies the requirement for deriving from boost::exception without requiring my_exception to derive from boost::exception.

If that is so, then that fact is omitted from the documentation for boost::enable_current_exception, please see:

Ah right, my mistake! It returns a type that derives from an unspecified type and T. The documentation is correct.

I do try to do my homework before posting here. :) Now, back to the original purpose of my postings: My Requirements: ---------------- To use Boost.Exception tools to make my exceptions transportable between threads without explicitly or implicitly deriving from Boost.Exception. So it seems I'm halfway there with "throw boost::enable_current_exception(my_exception());". Now I would like to rethrow from some catch site, it is my understanding then that I would need to use boost::rethrow_exception() (in order to stay within the parameters of my requirements). But boost::rethrow_exception requires a boost::exception_ptr reference (which seems can only be gotten via boost::current_exception). Now, does using "throw boost::enable_current_exception(my_exception());" with class my_exception which does not derive from boost::exception support the exception_ptr functionality that is need for boost::rethrow_exception? Thanks, Mostafa