why ... (three points) in catch block is exist?

Question

In the try catch statement we can do:

try{}
catch(...){}

As far as I know, ... means any exception.

My question is: Why the C++ standard chose this way (...) instead of just ()? while, for example, in functions if you do not need parameters you just put ():

void foo();

Is it related to variadic templates in any way?

In C++, unlike in C, `()` means `(void)` it doesn't mean any argument but rather a parameter list with no argument. — 101010, Apr 20 '16 at 08:10
[Read a book](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list). — Some programmer dude, Apr 20 '16 at 08:12
it is not duplicated of http://stackoverflow.com/questions/315948/c-catching-all-exceptions. please at least read the question — Humam Helfawi, Apr 20 '16 at 08:14
It's just an elegant way to say "anything". Maybe it could be better to use the `default` key-word in a similar way of switches... — Caduchon, Apr 20 '16 at 08:20

score 8 · Answer 1 · answered Apr 20 '16 at 08:11

It has nothing to do with variadic templates, because those came in C++11 whereas catch (...) existed from nearly the beginning (about two decades earlier).

As for why they chose (...) instead of (), you could ask Bjarne Stroustrup, but it hardly seems important. This feature isn't used all that often anyway. In C++, (...) usually means something like "Any number of things of any types" whereas () usually means "Nothing." Depending on your perspective, either one of these might be more preferred for "catch all exceptions."

It's really often used if you want something robust. – Caduchon Apr 20 '16 at 08:17 — Caduchon, Apr 20 '16 at 08:17

score 4 · Accepted Answer · answered Apr 20 '16 at 08:31

4

catch() would imply strongly that nothing was passed to that particular catch block.

But that is not true,

catch(...){
    throw;
}

actually re-throws the exception caught by ...

answered Apr 20 '16 at 08:31

Bathsheba

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nice point.. so internally the exception is cached by a hidden variable – Humam Helfawi Apr 20 '16 at 08:34

why ... (three points) in catch block is exist?

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