Hallo,
In experimenting on the design of an exception that cannot be caught I
wrote the following program:

class A {
    operator A& ();
};

int main() {
  try {
    throw A();
  }
  catch ( A & a ) {
  }
}

I expected it to generate an error, but to my surprise two out of my
three compilers accept this code. Who's right?

Thank you,
Nicola Musatti

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Nicola Musatti ha scritto:
> Hallo,
> In experimenting on the design of an exception that cannot be caught I
> wrote the following program:
>
> class A {
>     operator A& ();
> };
>
> int main() {
>   try {
>     throw A();
>   }
>   catch ( A & a ) {
>   }
> }
>
> I expected it to generate an error, but to my surprise two out of my
> three compilers accept this code. Who's right?

Why do you expect it to generate an error? I would have said the
opposite, because AFAIK binding an object of type A to an A& is a
"direct binding" and thus it won't involve a call to operator A&().
Moreover 15.3/3 does not consider the presence of conversion operators
when matching handlers to exception objects.

Which compiler gives the error and which error it is?

Ganesh

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