Re: [boost] Exception lib?

From: Bronek Kozicki (brok_at_[hidden])
Date: 2006-06-22 03:18:46

Emil Dotchevski wrote:
> catch( read_error & x )
> {
>     if( info * xi = dynamic_cast<info *>(&x) )

you do not need dynamic_cast here, or you could just put
   catch(info& x)
above read_error?

> catch( info & xi )
> {
>     xi.add( wrap_string<tag_src_file_name>(src_name) );
>     xi.add( wrap_string<tag_dst_file_name>(dst_name) );
>     throw;
> }

wow! I love it! I could add context information at higher levels of
application (when exception is "bubbling up") so that user gets relevant and
high-level information that he can match to what he was just doing. Nice!

> catch( io_error & x )
> {
>     if( info * xi = dynamic_cast<info *>(&x) )

again, why dynamic_cast?

> And finally, I indicated in my previous post that attachments can be added 
> directly in the throw-statement. 

maybe these attachments could be separate and more general utility? I played
with idea of employing similar functionality in implementation of the context
design pattern.

>         throw failed<fread_error>()
>             << wrap_errno()
>             << wrap_function("fread")
>             << boost::weak_ptr<FILE>(f);

although I'm one of these malcontents who wince seeing << or >> applied
anywhere where they look cool, here they not only look cool but also make a
lot of sense. Nice again!

B.