Re: [boost] Re: Boost.Assertion

From: Jesse Jones (jesjones_at_[hidden])
Date: 2001-04-17 18:44:26

At 8:43 PM +0200 4/17/01, Jens Maurer wrote:
>williamkempf_at_[hidden] wrote:
>>  If an exception is thrown the postcondition is almost gauranteed to
>>  fail.  As for single entry/single exit functions... they're needed
>>  for checking postconditions, not for checking invariants.  However,
>>  it would be nice if some mechanism could be devised that would allow
>>  postconditions to work regardless of the number of exit points.
>
>It seems to me that you want to find out in your "postcondition
>checking destructor" whether it was invoked because an exception was
>thrown (and stack unwinding is happening) or because the scope
>(function) was exited by normal means (i.e. return).
>
>The C++ standard provides the function std::uncaught_exception()
>which is true if your destructor is called during stack unwinding
>and false otherwise.  See section 18.6.4 in the C++ standard.
>
>Note that this feature is said not to work reliably on some
>compilers.

I thought std::uncaught_exception() was pretty much worthless, but I 
confess I don't know all the details (and the archives don't have 
much to say). Can we really use this inside a dtor to see if the 
stack is being unwound because of an exception?

   -- Jesse