Re: Boost.Threads draft library submission

From: williamkempf_at_[hidden]
Date: 2001-03-18 08:35:30

--- In boost_at_y..., "David Abrahams" <abrahams_at_m...> wrote:
> IMO using the question "is this an exceptional situation?" to 
decide whether
> to throw an exception has an attractive ring to it, but is usually a
> mistake. A more appropriate question to ask is: "do we want stack 
unwinding
> here?"
> 
> As a developer, if I have violated a precondition of a library I'm 
using, I
> don't want stack unwinding. What I want is a core dump or the 
equivalent - a
> way to inspect the state of the program at the point where the 
problem was
> detected. That usually means assert() or some equivalent.
> 
> I have sympathy with the idea of making resilient APIs which can 
stand up to
> nearly any kind of client abuse, but there is usually a significant 
cost to
> this approach. If someone wants that sort of protection, it can 
usually be
> provided as a layer on top of a simpler API.  I am utterly 
unsympathetic to
> half-measures, though. An API which promises resilience against 
some, but
> not all abuse is an invitation to disaster.

An assertion would be just such a disaster.  I understand what you're 
saying here, but the exception seems like the only viable solution in 
this situation to me.  Assertions will miss a large class of errors, 
since they'll be off when you really need them.  Error code returns 
would be even worse.  If there were another option it might be worth 
considering.

Bill Kempf