It's UB - there is nothing else to add about it - don't know where you are
inheriting all this.

On Wed, Nov 22, 2023 at 3:51 PM Lénárd Szolnoki via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On Wed, 2023-11-22 at 14:16 +0200, sasho648 via Std-Proposals wrote:
> > In my opinion if exceptions were used more it would be worthy to add
> > my suggestion - your solution is too verbose.
> >
>
> int f() {
> decltype(&func()) ptr = nullptr;
> try {
> ptr = &func();
> } catch(...) {}
>
> // use ptr here
> }
>
> I'm strongly against this proposal, as it introduces the concept of
> "uninitialized reference" that didn't exist before. Sure references can
> become stale and thus invalid, but they are not invalid right after
> their initialisation. This is essentially a null reference.
>
> The pointer makes it explicit that it might have a state other than
> referring to an object, and therefore safer. It also makes it possible
> (but not necessary) to check for this state.
>
> > On Wed, Nov 22, 2023 at 2:07 PM Lénárd Szolnoki via Std-Proposals
> > <std-proposals_at_[hidden]> wrote:
> > > On Wed, 2023-11-22 at 13:56 +0200, sasho648 via Std-Proposals
> > > wrote:
> > > > Because I only care about the exception thrown at `func()` and
> > > > don't
> > > > want to have exception handling for the rest of the code.
> > >
> > >
> > > int f() {
> > > const auto ptr = [&]() -> decltype(&func()) {
> > > try {
> > > return &func();
> > > } catch (...) {
> > > return nullptr;
> > > }
> > > }();
> > >
> > > // use ptr here, check for null, dereference, whatever
> > > }
> > >
> > > >
> > > > On Wed, Nov 22, 2023 at 1:54 PM Fabio Alemagna
> > > > <falemagn_at_[hidden]>
> > > > wrote:
> > > > >
> > > > >
> > > > > Il mer 22 nov 2023, 12:50 sasho648 via Std-Proposals
> > > > > <std-proposals_at_[hidden]> ha scritto:
> > > > > > Ok use-case I was thinking is actually:
> > > > > >
> > > > > > int f() {
> > > > > >
> > > > > > try (auto &ref = func()) {
> > > > > > } catch(...) {
> > > > > > return -1;
> > > > > > }
> > > > > >
> > > > > > // use ref here
> > > > > > }
> > > > >
> > > > > Why would you want to use ref after the whole try-catch block?
> > > > >
> > > > > If func() does't throw, you can use ref right after its call,
> > > > > within the try block itself.
> > > > >
> > >
>
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