throw

The throw statement is used to throw an exception and its value to a subsequent exception handler. A regular throw consists of the keyword throw and an expression. The result type of the expression determines which catch block receives control. Within a catch block, the current exception and value may be re-thrown simply by specifying the throw keyword alone (with no expression).

In the following example, the function call in the try block passes control to f(), which throws an exception of type Overflow. This exception is handled by the catch block, which handles type Overflow exceptions.

class Overflow {
                      // ...
public:
   Overflow(char,double,double);
};

void f(double x)
{
                      // ...
   throw Overflow('+',x,3.45e107);
}

int main() {
	try {
			              // ...
			f(1.2);
			              //...
	}
	catch(Overflow& oo) {
			              // handle exceptions of type Overflow here
	}
}