Re: [boost] Policy proposal: All user-visible exceptions should be thrown through BOOST_THROW_EXCEPTION

Subject: Re: [boost] Policy proposal: All user-visible exceptions should be thrown through BOOST_THROW_EXCEPTION
From: Emil Dotchevski (emildotchevski_at_[hidden])
Date: 2012-06-26 17:15:44

On Tue, Jun 26, 2012 at 10:24 AM, Brian Wood <woodbrian77_at_[hidden]> wrote:

> Pete Bartlett:
>
> < snip >
>
> > Cons for 1) and 2):
> > - Always paying for the cost of #including <boost/throw_exception.hpp>
> > - All libraries are dependent on - and therefore become vulnerable to any
> > future breakages (if any) in - Boost.Exception.
>
>
> Is there a penalty for single threaded applications here?  There's
> been discussion of the support for transferring exceptions between
> threads; are there aspects of that support that are unneeded in a
> single threaded context?
>

There are 3 aspects of boost::throw_exception:

1) it enables libraries to support BOOST_NO_EXCEPTIONS configurations,
2) it enables boost::error_info, and
3) it enables boost::exception_ptr.

1) and 2) have nothing to do with threads; 3) implements
std::exception_ptr, which mostly benefits multi-thread programs (until
compilers catch up with std::exception_ptr support.)

The cost imposed by libraries that use boost::throw_exception to programs
that don't use boost::exception_ptr or boost::error_info is that sizeof()
the exception object grows a little.

Emil Dotchevski
Reverge Studios, Inc.
http://www.revergestudios.com/reblog/index.php?n=ReCode