Hi Joel, Thanks for your reply! That is indeed the problem, I am wondering if there is a way to get around it so i can still use BOOST_THROW_EXCEPTION as it gives me the convenience of automatically appending function, file and line information. BOOST_THROW_EXCEPTION is a macro that is defined as follows (http://www.boost.org/doc/libs/1_40_0/libs/exception/doc/BOOST_THROW_EXCEPTIO...): #define BOOST_THROW_EXCEPTION(x)\ ::boost::throw_exception( ::boost::enable_error_info(x) <<\ ::boost::throw_function(BOOST_CURRENT_FUNCTION) <<\ ::boost::throw_file(__FILE__) <<\ ::boost::throw_line((int)__LINE__) ) Rethinking the problem from the perspective of your post, I did get something that compiles, but adds some syntax: BOOST_THROW_EXCEPTION(boost::enable_error_info(std::out_of_range("Matrix -=: Inputs do not have same shape")) << std_range_which(Rows()!=M.Rows()? "row" : "col")); Not ideal, it would be nice if i don't have to add the boost::enable_error_info() call manually, but I can work with it! Thanks, Dee On Sun, Oct 25, 2009 at 2:39 PM, joel wrote:

Diederick C. Niehorster wrote:

...

Simply doing BOOST_THROW_EXCEPTION(std::out_of_range("Matrix -=: Inputs do not have same shape")) <<            std_range_which(Rows()!=M.Rows()? "row" : "col"); does not work, nor does BOOST_THROW_EXCEPTION(std::out_of_range("Matrix -=: Inputs do not have same shape") <<            std_range_which(Rows()!=M.Rows()? "row" : "col"))

Maybe because std::out_of_range is not a boost::exception and dosn't support << ?

___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

_______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

On Sat, Oct 24, 2009 at 9:10 PM, Diederick C. Niehorster wrote:

Hi,

I have another question regarding the exception library. I would like to use the BOOST_THROW_EXCEPTION() macro, but also add some tags of my own at the throw site. How do I do this?

How would i rewrite the below? typedef boost::error_info std_range_which; throw boost::enable_error_info(std::out_of_range("Matrix -=: Inputs do not have same shape")) <<            std_range_which(Rows()!=M.Rows()? "row" : "col");

I would strongly recommend that you don't add a user message as error info. Just add the data the catch site needs to format a message. That said...

Simply doing BOOST_THROW_EXCEPTION(std::out_of_range("Matrix -=: Inputs do not have same shape")) <<            std_range_which(Rows()!=M.Rows()? "row" : "col"); does not work

The problem is that std::out_of_range does not derive from boost::exception. This is the precise situation boost::enable_error_info is designed for: BOOST_THROW_EXCEPTION(boost::enable_error_info(std::out_of_range("Matrix -=: Inputs do not have same shape")) << std_range_which(Rows()!=M.Rows()? "row" : "col"); Or (if you throw std::out_of_range a lot) just derive from it and boost::exception, then you don't need to use enable_error_info: struct my_out_of_range: virtual std::out_of_range, virtual boost::exception { }; BOOST_THROW_EXCEPTION(my_out_of_range() << std_range_which(Rows()!=M.Rows()? "row" : "col"); Emil Dotchevski Reverge Studios, Inc. http://www.revergestudios.com/reblog/index.php?n=ReCode

Emil Dotchevski wrote:

struct my_out_of_range: virtual std::out_of_range, virtual boost::exception { };

Why virtual inheritance ? -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

Hi Emil, On Sun, Oct 25, 2009 at 3:06 PM, Emil Dotchevski wrote:

Or (if you throw std::out_of_range a lot) just derive from it and boost::exception, then you don't need to use enable_error_info:

struct my_out_of_range: virtual std::out_of_range, virtual boost::exception { };

BOOST_THROW_EXCEPTION(my_out_of_range() << std_range_which(Rows()!=M.Rows()? "row" : "col");

This does not compile (on VS2008), giving me at call site: error C2512: 'my_out_of_range::my_out_of_range' : no appropriate default constructor available I have tried adding a default constructor, struct my_out_of_range: virtual std::out_of_range, virtual boost::exception {my_out_of_range(){};}; but then i get the error: error C2512: 'std::out_of_range::out_of_range' : no appropriate default constructor available I must be missing something painfully obvious here, but can't figure it out. Do you know what is going wrong? Best and thanks, Diederick