// Demonstration of difference between ANSI and Cfront rules
// for lifetime of compiler-generated temporary.
// Program prints "Cfront" when compiled with Cfront rules, 
// and "ANSI" when compiled by ANSI rules.

#include <iostream.h>

enum State {UNKNOWN,LIVE,DEAD};

class Object {
private:
    State* my_state;
public:
    Object( State* state ) : my_state(state) {*my_state=LIVE;}
    ~Object() {*my_state=DEAD;}
};

void f( const Object& c ) {}

main() {
    State state = UNKNOWN;

    // Compiler must generate temporary Object to pass as actual paramter to f.
    // The state of the object is tracked in state.
    f( &state );

    // Under ANSI rules, the temporary is destroyed after f(&state)
    // is evaluated, and thus is dead now.
    switch( state ) {
	case LIVE:
	    cout << "Cfront\n";
	    break;
	case DEAD:
	    cout << "ANSI\n";
	    break;
	default:
	    cout << "broken compiler\n";
	    break;
    }
    // Under Cfront rules, the temporary survives until the end of the
    // enclosing block.  Thus with Cfront, it is live up until here.
}