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From: Jesse Jones (jesjones_at_[hidden])
Date: 2001-04-18 18:03:28

At 7:42 AM -0400 4/18/01, David Abrahams wrote:
>----- Original Message -----
>From: "Jesse Jones" <jesjones_at_[hidden]>
>> 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?
>Yes (if the compiler conforms). The problem with uncaught_exception() is
>that it won't detect the case where you're inside a catch block which is
>going to rethrow the exception:
>try {
>catch(...) {
> // cleanup actions...
> // <=== uncaught_exception() is false here
> // more cleanup actions...
> throw;
>This condition is almost the moral equivalent of being inside a destructor
>during stack unwinding: the supposedly neccessary "more cleanup actions"
>won't be executed if you rethrow here. Also, the active exception is lost.

Hmm, well that's still useful. For example, it makes file classes a
bit easier to write. Instead of using a close() method you can do the
close in the dtor. If an error is returned you can throw if
uncaught_exception() returns true. Too bad CodeWarrior doesn't
support it...

   -- Jesse

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