A throw-expression with no operand in C++

    A throw-expression with no operand re-throws the exception currently being handled. Such an expression should appear only in a catch handler or in a function called from within a catch handler. The re-thrown exception object is the original exception object (not a copy). For example: 

 

try {
throw CSomeOtherException();
}
catch(...) {  // Handle all exceptions
// Respond (perhaps only partially) to exception
// ...
throw;       // Pass exception to some other handler
}

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   An empty throw statement tells the compiler that the function does not throw any exceptions. It is the equivalent to using __declspec(nothrow). For example:

// exceptions_trycatchandthrowstatements3.cpp
void empty() throw()
{
puts("In empty()");
}

void with_type() throw(int)
{
puts("Will throw an int");
throw(1);
}

int main()
{
try {
empty();
with_type();
}catch (int){
puts("Caught an int");
}
}

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