Re: [boost] The noexcept Specifier & Block

Subject: Re: [boost] The noexcept Specifier & Block
From: Peter Dimov (pdimov_at_[hidden])
Date: 2009-04-18 09:37:45

Alexander Terekhov:
> But exception translation can be done much more sensibly without
> unexpected().

... or not be done at all, which is even more sensible.

Regardless; in the pre-Abrahams era, when exception specifications were 
designed, the prevailing mindset was that the set of exception types a 
function can throw is of much importance, and that subsystems would design 
their own exception hierarchies and never throw something outside their 
hierarchy. Under these assumptions, exception specs and unexpected() do 
work. You can do

> void g() throw(Y)
> {
>    translate_any_exception_to<Y>(f);
> }

but this requires intrusive modifications of the g subsystem which you can 
sometimes avoid with a sufficiently smart unexpected handler.

It is not realistic to expect this behavior to be changed, but it might be 
possible to add another handler, separate from std::unexpected, that is 
invoked prior to stack unwinding. But I still do not understand your 
motivation for insisting that this is the correct way to do things. What 
specific practical problems does this solve?