[boost] Re: [boost::thread] locks, exceptions and assertions

From: Daniel Spangenberg (dsp_at_[hidden])
Date: 2003-07-21 05:28:55

Russell Hind schrieb:

> Jon Biggar wrote:
> >
> > In the thread lock case, the throw avoids the undefined behavior
> > entirely, since it doesn't ever do the underlying OS lock action that
> > causes the undefined behavior.
> >
>
> Wouldn't a throw in operator -> of shared_ptr achieve the same thing?

In this case, shared_ptr could not provide the "no throw" guarantee for
dereferencing the pointer. This is usually an important requirement for
smart pointers.
My own discussion in c++-moderated with David Abrahams and others
convinced me, that in most cases like this you have to decide the following:

Which throw guarantees do we want/need?

- If "no throw" is importand, use assert
- otherwise use a well-documented exception

Yours,

Daniel