try-catch usage

[Obnoxious User]

Why does this:

try
{
throw 1;
}
catch(...)
{
handle_exception();
}

works as expected (exception is caught in the catch block)

and this:

try
{
throw;

I doubt this statement is even allowed here. It is used within
catch handlers to rethrow the exception so it can be catched
again somewhere.

 

[vmnvmcxbv]

Why does this:

try
{
throw 1;
}
catch(...)
{
handle_exception();
}

works as expected (exception is caught in the catch block)

and this:

try
{
throw;
}
catch(...)
{
handle_exception();
}

crashes application? Isn't catch(...) supposed to catch _everything_?

FWIW - I use VC++ 2008

 

[Nick Keighley]

Why does this:

try
{
    throw 1;}

catch(...)
{
    handle_exception();

}

works as expected (exception is caught in the catch block)

and this:

try
{
    throw;}

catch(...)
{
    handle_exception();

}

crashes application? Isn't catch(...) supposed to catch _everything_?

FWIW - I use VC++ 2008

you didn't throw _everything_ you threw nothing.
I believe the "naked" throw should only be used
for a rethrow of an exception that's beeen caught.

 

[Ali Karaali]

Why does this:

try
{
    throw 1;}

catch(...)
{
    handle_exception();

}

works as expected (exception is caught in the catch block)

and this:

try
{
    throw;}

catch(...)
{
    handle_exception();

}

The catch can catch everything but you don't throw anything.
So calling std::terminate() function

 

[red floyd]

Why does this:

try
{
    throw 1;}

catch(...)
{
    handle_exception();

}

works as expected (exception is caught in the catch block)

and this:

try
{
    throw;}

catch(...)
{
    handle_exception();

}

crashes application? Isn't catch(...) supposed to catch _everything_?

Per 15.1/8, "If no exception is presently being handled, executing a /
throw-expression/ with no operand calls terminate()."

In other words, a "throw;" must occur inside a catch block, or you
will be terminated.

 

[Michal]

Per 15.1/8, "If no exception is presently being handled, executing a /
throw-expression/ with no operand calls terminate()."

Hallo Red

I like Your answer very much!
Could YOu tell me where does this sentence go from?
best regards
Michal

 

[Erik Wikström]

Hallo Red

I like Your answer very much!
Could YOu tell me where does this sentence go from?

It's from the ISO C++ standard, section 15.1, the eighth paragraph.

 

[Michal]

It's from the ISO C++ standard, section 15.1, the eighth paragraph.

thanks for the answer
best regards